Department of Physics Magazine 2019 by College of Arts and Sciences at Ohio State

NEWS FROM THE DEPARTMENT OF

PHYSICS AUTUMN 2019

SMALL SKYRMIONS SPIN BIG IDEAS [PAGE 6]

57TH ANNUAL ALPHEUS SMITH LECTURE: OCT. 23, 2019

CLIMATE CHANGE AND INNOVATIVE PATHS TO A SUSTAINABLE FUTURE Nobel Laureate Steven Chu The industrial and agricultural revolutions have profoundly transformed the world, but the unintended consequence of these revolutions is that humans are changing the climate of Earth. I will briefly describe new data on climate change, before turning to the rapidly changing energy landscape and how science, engineering and innovation can provide a path to a sustainable and prosperous future. NOBEL LAUREATE STEVEN CHU is the William R. Kenan, Jr. Professor of Physics and Professor of Molecular & Cellular Physiology in the Medical School at Stanford University. Chu was the 12th U.S. Secretary of Energy from January 2009 until the end of April 2013. As the first scientist to hold a Cabinet position and the longest serving Energy Secretary, he recruited outstanding scientists and engineers into the Department of Energy. Prior to his cabinet post, he was director of the Lawrence Berkeley National Laboratory, where he was active in the pursuit of alternative and renewable energy technologies. Chu is the co-recipient of the 1997 Nobel Prize in Physics “for development of methods to cool and trap atoms with laser light.”

THE ALPHEUS SMITH LECTURE HAS BEEN BRINGING LEADING-EDGE WORK OF NOBEL LAUREATES AND OTHER PROMINENT PHYSICISTS TO THE COMMUNITY SINCE 1960. THE FREE, PUBLIC LECTURE SERIES IS ENDOWED BY ROBERT SMITH TO HONOR HIS FATHER, PHYSICS PROFESSOR ALPHEUS W. SMITH.

2020 SMITH LECTURE DONNA STRICKLAND

2018 Nobel Laureate “for their method of generating high-intensity, ultra-short optical pulses” The sharp beams of laser light have given us new opportunities for deepening our knowledge about the world and shaping it. In 1985, Gérard Mourou and Donna Strickland succeeded in creating ultrashort high-intensity laser pulses without destroying the amplifying material. First they stretched the laser pulses in time to reduce their peak power, then amplified them, and finally compressed them. The intensity of the pulse then increases dramatically. "Chirped pulse amplification" has many uses, including corrective eye surgeries. Donna Strickland was born in Guelph, Ontario, Canada. She became interested in laser and electrooptics early and studied at McMaster University in Hamilton, Ontario. She pursued her doctoral studies in the U.S. at the University of Rochester, where she did her Nobel Prize awarded work. She obtained her PhD in 1989. She subsequently has worked at Princeton University and since 1997 at the University of Waterloo in Canada.

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CONTENTS 4 5 6 9 10 12 13 13

ON THE COVER

INSIDE BACK COVER

A LETTER FROM THE CHAIR INSIDE THE DEPARTMENT’S STRATEGIC PLANNING SMALL SKYRMIONS SPIN BIG IDEAS TWO PHYSICS STUDENTS NAMED GOLDWATER SCHOLARS PROFESSIONAL DEVELOPMENT OPPORTUNITIES WHAT THE PHYSICS?! UNDERGRADUATES SHARE THEIR SUMMER EXPERIENCES

IN THE DEPARTMENT PHYSICS BY THE NUMBERS SUPPORT THE DEPARTMENT

SKYRMIONS AT THE SURFACE OF MNGE CRYSTALS. Skyrmions are a swirling arrangement of magnetic moments that can behave like a particle. They arise in magnetic materials with strong spin orbit coupling and broken inversion symmetry, such as MnGe. The interactions that drive their formation enable them to be extremely stable (~ 10 years) and much smaller (< 10nm) than the typical magnetic domains used inside memory devices such as hard drives. Because of this, skyrmions are interesting for use in non-volatile, ultra-high-density storage devices. At these nanoscopic scales, visualizing and manipulating magnetism is quite challenging. However, spin-polarized scanning tunneling microscopy (SPSTM) is sensitive to and can influence magnetic ordering with resolution down to 0.5nm. The cover image is an SPSTM map of a “target skyrmion” in MnGe where the moments wind up more than typical skyrmions seen in other magnetic systems. Here, green/red contrast indicates magnetic moments pointing “up” and blue/black contrast shows moments pointing “down” with tumbling moments in between. The central bright core is surrounded by several concentric rings that collectively act as a single object. These special skyrmionic configurations can be engineered using STM to tune their properties to be particularly useful. Material systems with different physical and magnetic properties are being grown and explored by the DARPA team at Ohio State in an effort to develop the ideal system for skyrmion devices. To learn more, turn to the full story on page 6. CREATED BY JACOB REPICKY

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A LETTER FROM THE CHAIR Dear Friends of Physics, It is a pleasure to provide you with the latest addition of our Department of Physics magazine. As you can see in the pages that follow, we have much to be proud of regarding the accomplishments of our students and faculty. The stories in this issue give you a flavor of what is happening in this large and dynamic department. We are adding two new exceptional faculty this year. Alexandra Landsman comes to us from the Max Planck Institute in Dresden, and Brian Skinner comes from MIT. We look forward to having both of them join our faculty and bring their unique talents to the department. In addition, the existing faculty continue to win accolades for their research and teaching. Once again, we have several faculty that have been recognized for their exceptional teaching and scholarship at the university. Others have achieved accolades on the national and international scale.

FROM QUARKS TO THE COSMOS — FACULTY IN THE DEPARTMENT OF PHYSICS EXPLORE THE UNIVERSE ON THE SMALLEST SCALES, EXAMINING THE BUILDING BLOCKS OF NATURE AND EXOTIC NUCLEAR MATTER, AND ON THE LARGEST SCALES, STUDYING THE EVOLUTION OF THE COSMOS INFLUENCED BY DARK MATTER AND DARK ENERGY.

Our student programs continue to grow in popularity. We graduated about 70 undergraduate majors and 30 PhD students last academic year. These are some of the largest classes ever. With about 140 new undergraduate majors entering the last two autumn semesters, we are poised for even more graduates in the future. These students are winning awards for their accomplishments while in the program, and we are continuing to attract high-caliber students to both our graduate and undergraduate programs. Last year was an important year for the department. We underwent an external program review, which involved a tremendous amount of work by the faculty and staff. We had detailed discussion about our programs — what we do well and what needs improvement. These frank discussions have led to a strategic “Plan of Action” for the next five to seven years. We have some excellent ideas about how to move our department forward, and we have shared some of these ideas in an article. I am very excited by the future potential of the department and look forward to sharing our achievements in future issues. We hope you enjoy this latest issue of the Department of Physics magazine. Please follow us on social media if you would like to know more. Thank you for your support that helps make these achievements possible. As always, please feel free to stop by the department and experience in person the exceptional work being done.

Brian L. Winer Chair

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INSIDE THE DEPARTMENTâ&#x20AC;&#x2122;S STRATEGIC PLANNING Last year, the Department of Physics implemented an external academic program review, the first since 2010. A thorough self study highlighted the strengths and weaknesses of the department and brought clarity to its strategic path forward. In September 2018, a review committee visited campus and met with department stakeholders and university leaders. With input from the external committee, the department formulated a plan of action for approximately the next five years. The department will take steps on many different fronts. A few key areas of focus are a five-year hiring plan for new faculty, revisions to the structure of our graduate program and improvements to our undergraduate majors program.

HIRING PLAN: The department hiring plan is the outcome of more than two years of effort to identify key areas for future hiring. The plan consists of 10 to 15 new hires that will maintain our breadth by stabilizing core areas, grow areas poised to attract additional or new center-like funding and initiate efforts that will move the department into exciting new areas. We plan to hire in a range of specialties: nuclear, particle, astroparticle, AMO, biophysics, neutrino/dark matter, gravitational and quantum information. This hiring exercise will be an opportunity to improve the diversity of the department, and we have set the goal of doubling (from five to 10) the number of Columbuscampus women faculty members in the next five years. Given the magnitude of the hiring, it will significantly shape the department for the next 25 to 30 years and is an opportunity that arises rarely.

GRADUATE PROGRAM: We are exploring several different avenues of improvements to our graduate program and are considering instituting a new qualifying procedure that includes an exam. This would ensure

all graduate students are starting with a solid foundational understanding in the field. In conjunction with this, we are reviewing the curriculum of the core graduate courses for content, level and grading norms. The Graduate Studies Committee has conducted detailed surveys of these areas at peer institutions. Our goal is to enhance the preparation our graduate students for cutting-edge research and prepare them for 21st century careers in the field.

UNDERGRADUATE MAJORS PROGRAM: The size of our undergraduate majors program has more than doubled in the last 10 years to over 500 students. Through strategic planning, we have identified several areas for improvement in our program. First, to improve the diversity of our student population, we must expand our efforts to recruit and retain underrepresented groups. The department currently has a variety of programs that work toward the goal of increasing diversity in the student population. Recently, a program called Polaris, started by a group of graduate students, pairs early program undergraduates with graduate student mentors to help navigate the challenges of a physics major. In addition, we are considering programs in peer-led team teaching and a summer program for new students. To help coordinate these efforts, we have hired a new diversity coordinator to oversee our efforts. Second, we have embarked on an overhaul of our laboratory sequence for our majors. We are updating the labs to use more modern programming, equipment and data analysis techniques. In addition, we will move these laboratory experiences earlier in the studentsâ&#x20AC;&#x2122; academic career. We seek to provide early experience with modern toolsets so students are better prepared to participate in research labs and the advanced lab courses their senior year.

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SMALL SKYRMIONS SPIN BIG IDEAS BY ALISON SCOTT In a testament to the highly collaborative materials community at Ohio State, a team of faculty in physics and materials science and engineering were awarded a $6.34 million grant from the Defense Advanced Research Projects Agency (DARPA). Phase One of the funding began in February 2018, and Phase Two was recently approved to run through July 2021. The team consists of Mohit Randeria, professor of physics and principal investigator on the grant, and co-investigators Jay Gupta, associate professor of physics; P. Chris Hammel, professor of physics, Ohio Eminent Scholar and director of the Center for Emergent Materials (CEM); Roland Kawakami, professor of physics; David McComb, professor of materials science engineering and Ohio Research Scholar; and Fengyuan Yang, professor of physics. The Ohio State team was one of a handful worldwide, and the only team housed at a single institution, selected to participate in DARPA’s Topological Excitations in Electronics (TEE) program. The TEE program focuses on funding research with an eye toward advancements in memory, logic, sensors and quantum information processing. The Ohio State DARPA team studies the role of magnetic skyrmions in prototype memory devices for data storage.

A central motivation for this effort is that the storage density of conventional magnetic hard drives is limited by how small the individual bits can be made. Like all materials, materials used for memory have electrons that spin, which creates tiny magnetic moments in the material. When the moments align, microscopic magnetization is created. Current technology relies on these moments synchronizing in up-and-down patterns, which translate to binary ones and zeroes in data storage. Once you create these binary digits — or bits — you are able to read, write, erase, store or otherwise manipulate data. At today’s storage densities, the magnetic bits are about 20 nanometers (nm) in diameter and cannot be made much smaller without sacrificing stability. Magnetic skyrmions have been realized at low temperatures down to 1nm in diameter, which is promising for magnetic memories with even higher storage densities. “One of the challenges in magnetic memories is how to make denser memories that are nonvolatile, volatile meaning susceptible to temperature fluctuations,” said Randeria. “You don’t want your data to be erased or corrupted just because you’re at room temperature. So that’s where the idea of skyrmions comes in from the point of view of applications.”

THREE-DIMENSIONAL VIEW OF SKYRMIONS. SURFACES OF MATERIALS ARE NEVER TRULY FLAT. IN CRYSTALLINE MATERIALS, THE SURFACE IS MADE UP OF ATOMICALLY FLAT REGIONS CALLED “TERRACES” THAT ARE SEPARATED FROM EACH OTHER IN HEIGHT BY INTEGER MULTIPLES OF THE ATOMIC UNIT CELL. THESE STEPS LOCALLY DISTURB THE ORDERING OF THE CRYSTAL STRUCTURE AND CAN HAVE PROFOUND EFFECTS ON THE MAGNETIC BEHAVIOR NEARBY. THE SPSTM MAP SHOWN HERE DEPICTS A THREE-DIMENSIONAL, TOPOGRAPHIC VIEW OF SUCH A STEP WITH A TARGET SKYRMION NEARBY ON EACH TERRACE. OUR GOAL IN THESE STUDIES IS TO DETERMINE HOW THE PHYSICAL STRUCTURE AT THE SURFACE AFFECTS HOW SKYRMIONS FORM AND BEHAVE WHEN MANIPULATED WITH ELECTRIC CURRENTS OR MAGNETIC FIELDS. CREATED BY JACOB REPICKY.

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PROFESSOR ROLAND KAWAKAMI, RESEARCH ASSOCIATE CAMELIA SELCU, PROFESSOR P. CHRIS HAMMEL AND ASSOCIATE PROFESSOR JAY GUPTA (FROM LEFT TO RIGHT) OBSERVE A SPIN-POLARIZING SCANNING TUNNELING MICROSCOPE USED TO IMAGE SKYRMIONS FOR THE DARPA PROJECT.

In magnetic materials, a skyrmion is a compact object where the spins do not arrange themselves into up-and-down patterns; they have something called spin texture. In this context, texture means the spin is swirling in a pattern, much like the way water moves around a whirlpool. This property makes small skyrmions more stable than other types of magnetic spins. “Unlike other types of spins that are susceptible to thermal fluctuations, this whirl of spins has something called topological stability,” Randeria said. “Making small changes here and there doesn’t change the fact that it’s still whirling because there’s some structure to the pattern.” The DARPA team is a case study in how the collaborative materials culture at Ohio State can grow an idea from seed to

maturity. Spurred by rapid developments in the field, Randeria first became interested in skyrmions just over five years ago while investigating potential new research areas in magnetism and related applications. These notions were “sprouted” by a new graduate student in the group with the support of summer funding by the CEM, a Materials Research Science and Engineering Center (MRSEC) at Ohio State funded by the National Science Foundation (NSF). As their theoretical work developed, synergies with experimental work in magnetism naturally arose and were supported with additional seed funding from Ohio State’s Materials Research Seed Grant Program, a joint effort by the CEM, the Center for Exploration of Novel Complex Materials (ENCOMM) and the Institute for Materials Research (IMR). This funding supported initial publications from the group, as well as preliminary results that competitively positioned the group to vie for external funding opportunities.

AN EXAMPLE OF MAGNETIC SPIN TEXTURE IN A SINGLE SKYRMION. CREATED BY JAMES ROWLAND AND MOHIT RANDERIA.

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The announcement of the DARPA TEE program in 2017 was a recognition that magnetic skyrmions had great potential for next-generation storage and information processing but required ambitious efforts to realize this potential. The complementary expertise of the Ohio State team at this point in materials synthesis, magnetic microscopy and theoretical modeling was a natural match to the DARPA program requirements, and the team was able to put together a strong proposal to win the award. Phase One of the project, which entailed the first yearand-a-half of the award period, tasked the team with demonstrating skyrmions at 10nm in diameter that were stable at room temperature, a daunting goal that had not been demonstrated in any material prior to the start of the DARPA program. Achieving this goal required breakthroughs in materials development, magnetic characterization down to the nanoscale and theoretical modeling. On the imaging side, for example, spin-polarized scanning tunneling microscopy was demonstrated by Gupta’s group to image magnetic skyrmions in materials grown by the Kawakami and Yang labs. In concert with magnetic force and transmission electron microscopy imaging by the Hammel and McComb groups, the DARPA team has been able to demonstrate less than 10nm

skyrmions in a variety of materials that are also stable at room temperature. This achievement required the focused efforts of a highly collaborative team of faculty, graduate students, postdoctoral researchers and staff scientists. “I really cannot say enough about the students and postdocs,” Randeria said. “They worked especially hard to get progress on Phase One. We also had staff scientists [Camelia Selcu and Denis Pelekhov] from the NanoSystems Laboratory, who were very involved and were participating because they were super excited about the science.” Phase Two of the DARPA project focuses on optimizing the skyrmions and materials created in Phase One and incorporating them into a prototype memory device. Though the next phase’s research is sure to require even more collaboration and inventiveness from the investigators and their students, the team enjoys the collaborative interactions and the challenging goals posed by DARPA. “DARPA gives you these really strict deadlines and focus points that has fostered close collaboration among everyone on the team,” Gupta said. “That’s probably the most rewarding aspect of this program.”

THESE PHOTOS SHOW THE INTERACTIONS BETWEEN FACULTY, STUDENTS AND RESEARCH STAFF AT A RECENT DARPA PROJECT MEETING. THE IMAGE ON THE TOP RIGHT FEATURES PROFESSORS DAVID MCCOMB AND MOHIT RANDERIA IN A ONEON-ONE CONVERSATION. THE IMAGE ON THE TOP LEFT SHOWS PROFESSOR FENGYUAN YANG WITH GRADUATE STUDENTS AND NSL DIRECTOR DENIS PELEKHOV IN THE BACKGROUND LISTENING IN. THE IMAGE TO THE LEFT SHOWS GRADUATE STUDENTS TAKING PART IN THE DISCUSSION.

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TWO PHYSICS STUDENTS NAMED GOLDWATER SCHOLARS

KYLE DEBRY An Ohio State honors student has been recognized by the Barry M. Goldwater Scholarship and Excellence in Education Program. Sophomore Kyle DeBry was named a 2018 Goldwater Scholar, the most prestigious national award for undergraduate researchers in science, math and engineering. Goldwater Scholars receive an award to cover the cost of tuition, fees, books, and room and board up to a maximum of $7,500. Kyle, an honors student and Valentino Scholar majoring in engineering physics, plans to conduct research in the field of quantum information science, particularly in the area of quantum computing. He is currently working on a research project studying quantum key distribution and quantum machine learning under the direction of Daniel Gauthier and Gregory Lafyatis. In the course of this project, Kyle has developed a way to fabricate superconducting coaxial cables for use in his laboratory's cryostat to reduce the heat load on the coldest stage. Additionally, Kyle has fabricated superconducting nanowire single photon detectors (SNSPDs). Kyle intends to pursue a PhD, during which he will conduct experimental research with the goal of creating practically useful quantum computers.

CAROLINE JIPA Junior physics and chemistry major Caroline Jipa is one of four Ohio State students to receive 2019 Barry M. Goldwater Scholarships. Caroline aims to earn an MD and PhD in biophysics to conduct research on cellular pathways for regenerative medicine using biophysics techniques at an academic medical center. Professor Michael Poirier is advising Caroline's research. Her research is summarized here: For efficient storage and protection, DNA in cells is packaged into chromatin. The base unit of chromatin in the Nucleosome, 147bp of DNA wrapped around a histone octamer core. Different levels of DNA packaging affect the accessibility of DNA and gene expression. For example, the DNA in a Nucleosome is inaccessible to normal transcription factors (TFs). A subgroup of TFs have high affinity to sites in nucleosomes. To study the mechanism of these TFs, we examine Reb1 and CBF1, in S. Cerevisiae. We characterize the binding kinetic to nucleosomes vs free DNA via electrophoretic mobility shift assays, ensemble and single molecule FRET and PIFE measurements. We find Reb1 and CBF1 have similar affinity to DNA and Nucleosomes but different kinetics, such as longer dwell times to nucleosomes. We find that these behave similar to human Pioneer Factors, suggesting a conserved mechanism. PHYSICS.OSU.EDU

PROFESSIONAL DEVELOPMENT OPPORTUNITIES

CODING BOOT CAMPS In May 2019, the Erdős Institute ran its Cőde coding boot camps for the second year. Supporters included Ohio State’s Department of Mathematics, TGDA (Topology, Geometry and Data Analysis), the Department of Physics, the Department of Astronomy and the Center for Cosmology and Astroparticle Physics (CCAPP), plus companies Root and CoverMyMeds. In total, 60-plus graduate students and Ohio State graduate alumni, including substantial representation from physics, astronomy and CCAPP, participated in month-long courses on the Python and R programming languages. The boot camp culminated in a group project showcase where nine teams presented on projects ranging from predicting advertisement microauction success to machine-learning models classifying bird songs. The winning team was Caleb Dilsavor (mathematics), Dananjaya Liyanage (physics) and Hiran Wijesinghe (physics). The boot camps are closely connected to the Invitations to Industry seminar series, run by CCAPP for physics and astronomy participants, in partnership with the Erdős Institute.

BIG DATA ANALYTICS IN PHYSICS A substantial fraction of both undergraduate and graduate students in the Department of Physics seek employment in the private sector upon graduation, and many of these students find jobs in computer science or engineering related fields. In addition, there is a tremendous need for workers with skills in machine learning and artificial intelligence techniques. In response to this, the Department of Physics offered a new course, Big Data Analytics in Physics, during the spring semester of 2019. Developed by Professor Richard Hughes, this course introduces machine learning and advanced algorithms, with an emphasis on practical, physics-based applications using publicly available data sets. The goal is to introduce data science for students interested in pursuing this as a career option and/or apply these techniques in a research environment. The makeup of the class is approximately 40% graduate students and 60% undergraduate. A crucial component of this course is the partnership with the Ohio Supercomputer Center (OSC). OSC provides a modern computing environment, access to state-of-the-art tools, and a farm of thousands of CPUs and hundreds of GPU-enabled machines. Students not only get to learn how to solve 10

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complex, machine-learning problems, they also gain valuable experience working with a high-performance computing system. A highlight of the course is a final project in which each student picks their own “big data” problem and uses the techniques they learned in the class to find a machine-learning solution. Examples of such projects include the application of image classification in a biophysics analysis, the classification of galaxy types and the application of a convolutional neural network to particle physics searches.

SCIENTIFIC THINKERS Scientific Thinkers is an outreach program that engages Columbus’ elementary school students through hands-on science lessons taught by STEM undergraduate, graduate and faculty volunteers. The program was created in 2010 by professor of physics Nandini Trivedi, co-leader of a Center for Emergent Materials (CEM) Interdisciplinary Research Group. CEM is a National Science Foundation (NSF)-funded Materials Research Science and Engineering Center (MRSEC). Scientific Thinkers motivates the next generation of scientific thinkers from parts of our society that are often underrepresented in STEM fields and has been administered by the CEM for a number of years, recently transitioned to a student organization. Scientific Thinkers allows volunteers to have a more formal network and leadership opportunities to provide feedback and insights for the future direction of the program. The organization, advised by CEM Education Program Director Michelle McCombs, has an engaged executive board that is always seeking ways to improve the program and have a lasting positive impact on the Columbus community. One of the organization’s largest events is their annual Science Day at Innis Elementary School, which serves first- through fifth-graders. On Science Day, each student engages in a variety of science lessons led by around 50 volunteers from Ohio State and Franklin County Metro Parks. Some of the students’ favorite lessons include a Van de Graff generator and the liquid nitrogen show. Another annual event, Science Night, allows parents and siblings to also engage with teachers and Ohio State scientists. “Scientific Thinkers is a great opportunity for me to branch out and gain valuable experience teaching an age demographic that I interact with on a regular basis when at work,” said current president Nathan Zimovan. “It’s a highlight of my week when I get to provide a little excitement to the students who crave hands-on and unique experiences that are different from what they’re used to.”

ELEMENTARY SCHOOL STUDENTS WORK TOGETHER TO CREATE AN EMERGENCY FLASHLIGHT FOR ONE OF SCIENTIFIC THINKERS’ ACTIVITIES.

CENTER FOR EMERGENT MATERIALS DIRECTOR P. CHRIS HAMMEL AND VOLUNTEERS WITH INNIS ELEMENTARY SCHOOL STUDENTS DURING SCIENCE DAY 2018.

CEM INTERDISCIPLINARY RESEARCH GROUP CO-LEAD FENGYUAN YANG, PROFESSOR OF PHYSICS, AND A STUDENT VOLUNTEER DEMONSTRATE THE VAN DE GAFF GENERATOR TO AN INNIS ELEMENTARY SCHOOL STUDENT DURING SCIENCE DAY 2018.

SCIENTIFIC THINKERS VOLUNTEER ADAM AHMED, A POSTDOC IN PHYSICS, GETTING READY TO BREAK A RACQUETBALL THAT HAS BEEN FROZEN WITH LIQUID NITROGEN FOR INNIS ELEMENTARY SCHOOL STUDENTS DURING SCIENCE DAY 2018.

Photos courtesy of Scientific Thinkers and The Ohio State University.

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WHAT THE PHYSICS?! BY DENISE BLOUGH In his office at Harvard University, 2008 alumnus Greg Kestin has a chair with an ominous message: “2.5 Ways to Die in a Black Hole.” The American Institute of Physics gave Kestin the chair as part of an award for his work on a video of the same name, produced in 2014 by the PBS science series NOVA. In addition to teaching physics at Harvard, Kestin currently works for PBS NOVA hosting a video series — which has more than 20 million YouTube views — called “What The Physics?!” Kestin’s first interaction with PBS occurred during his doctoral studies at Harvard, when he was brought on as an intern for NOVA to collaborate with the chief editor on a two-hour special about black holes and the answers they may hold about the evolution of the universe. The product, “Black Hole Apocalypse,” was released in 2015 and has since been added to Netflix and nominated for an Emmy. “After I graduated I stayed in communication with NOVA PBS as an independent contractor and I eventually became an associate producer making various videos,” Kestin said. “Every once in a while, I would host a live event on YouTube where the audience could ask me physics questions, and after doing a couple of those and a couple of physics videos, we decided to combine them, and I started hosting ‘What The Physics?!’ in 2016.” After earning his bachelor of science in physics from Ohio State, Kestin completed research programs at the Princeton Plasma Physics Laboratory and California Institute of Technology. For his PhD at Harvard, he studied under physicist Howard Georgi and completed his dissertation on light-shell theory. 12

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Kestin said he has his undergraduate experience at Ohio State to thank for his success in academia and popular science. “There is no way I would be where I am without the support that I got from the faculty at Ohio State,” he said. “When Professor Ulrich Heinz brought me into his lab, he really trusted that I could do the really hardcore research that graduate students were doing, and I published four or five papers as an undergraduate with him. Without those publications, I don’t know if the graduate schools I applied to would have seen my potential as a researcher based on grades alone.” The feeling is mutual for Heinz, a Distinguished University Professor in the Department of Physics who still has fond memories of Kestin. “Greg was an extraordinarily gifted and highly motivated student. He learned quickly and soon became an equal member of my research group,” Heinz said. “He also possesses a rare gift for popularizing science and explaining difficult concepts in everyday language using unforgettable real-life examples.”

THE AMERICAN INSTITUTE OF PHYSICS GIFTED GREG KESTIN THIS CHAIR AS PART OF AN AWARD FOR HIS WORK ON A VIDEO TITLED “2.5 WAYS TO DIE IN A BLACK HOLE,” PRODUCED IN 2014 BY THE PBS SCIENCE SERIES NOVA. THE CHAIR NOW SITS IN KESTIN’S OFFICE AT HARVARD UNIVERSITY.

While a Buckeye, Kestin also showed some of his future colors by producing a comedic physics show that people from the department gathered to watch at the Physics Research Building, Kestin said, adding how thankful he is for professors like Linn Van Woerkom who supported the creative endeavor. Currently, Kestin is teaching the largest physics course at Harvard, conducting education research and working on 15-minute mini documentaries for NOVA and “What The Physics?!” that explore humans’ role in physics. “It’s really nice to be at both Harvard and PBS, because my conversations with my colleagues often lead to these videos,” he said, citing a recent “What The Physics?!” video inspired by a phenomenon one of his peers discovered where a ball can be rolled uphill instead of downhill. “A lot of the ideas come from either the theoretical knowledge from my research in theoretical physics or by talking with my colleagues who are excellent researchers and instructors.” When asked what advice he would give to students, Kestin said the most important thing is allowing oneself to be unique.

A LOT OF THE IDEAS COME FROM EITHER THE THEORETICAL KNOWLEDGE FROM MY RESEARCH IN THEORETICAL PHYSICS OR BY TALKING WITH MY COLLEAGUES WHO ARE EXCELLENT RESEARCHERS AND INSTRUCTORS.

“Allowing yourself to be different and unique and honest about yourself about what you want can get you where you want to go more than fitting in, I think almost always,” he said, adding that students should always strive to find professors or mentors who are open and caring.

think physicist Richard Feynman would say, which is that you need to build your own way of understanding science and physics. There’s a language that is traditional in any field — the way that people talk about the kinds of puzzles or some subfield of physics — but I found that to really understand, you almost need to think of your own language to remember and understand the science.

As for those aspiring toward success in physics or popular science (or both), “I think the biggest piece of advice is one I

“If you think about it differently you might see a different puzzle or how to solve one in a way that nobody else does.”

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UNDERGRADUATES SHARE THEIR SUMMER EXPERIENCES On average, 70% of students in physics or engineering physics will complete at least one research or internship experience before they graduate. We caught up with four undergraduates who discussed the programs they participated in this summer.

ARI JOSEPHSON Ari spent his summer at Northern Illinois University and Argonne National Lab as part of the NSF-funded Research Experience for Undergraduates (REU) program. “My project is on photon identification at the ATLAS detector at CERN. I’m working with a grad student who has developed some machine learning tools that are better at rejecting background events and my job is to apply these tools to a specific analysis involving the decay of the Higgs boson,” he siad. “The end goal is to show a statistically significant improvement in background rejection compared to the current photon identification standard ATLAS uses.”

DANIEL PHARIS Daniel (pictured left) participated in the 12-week long DAAD RISE program at Johannes Gutenberg University Mainzin in Germany. “The project I’m working on is using graphene nanoribbons to make field-effect transistors,” he explained. “A lot of my research group’s work is similar to the research people are doing at Ohio State, although I’m doing different things in the lab here than I do at Ohio State so the change is fun. I’ve been doing some traveling within Germany, as well as a bit of international travel. I was in Strasbourg for about a week for an annual graduate student seminar, which I really enjoyed. I also am going to Switzerland to do some hiking.”

IN THE DEPARTMENT

FACULTY AWARDS, HONORS AND PROMOTIONS JOHN BEACOM NAMED HENRY L. COX PROFESSOR OF PHYSICS AND ASTRONOMY

NANDINI TRIVEDI RECEIVES OHIO STATE DISTINGUISHED SCHOLAR AWARD

John Beacom, College of Arts and Sciences Distinguished Professor of Physics and Astronomy and Director of the Center for Cosmology and Astro-Particle Physics (CCAPP) was named the second recipient of the Henry L. Cox Professor of Physics and Astronomy in 2018. The annual income from this endowment supports exceptional and cutting-edge research for a faculty member in the Department of Astronomy and/or the Department of Physics on a five-year rotating basis. Henry Cox was a graduate of Ohio State with an MS in 1951 and his PhD in 1955, both in physics.

With this award, the university recognizes and honors six faculty members annually who demonstrate scholarly activity, research or other creative works which represent exceptional achievement in their fields. Recipients of the award receive a $20,000 research grant and a $3,000 honorarium to pursue their scholarly activity.

DEPARTMENT OF PHYSICS

JOEY MASTERS Joey participated in the 10-week long summer research program in the Department of Physics. “This summer, I worked in Dr. Roland Kawakami’s condensed matter group. I used different methods of exfoliating van der Waals materials to consistently get thin films of hexagonal boron nitride (hBN) and Fe3GeTe2 (FGT). I then learned to take these thin films and stack them in different combinations depending on what the group wanted to measure. The stacked materials, or devices, are used to induce electron tunneling, create single photon emission and more, to better understand how these materials interact with electrons and light. Understanding these materials will have many applications such as creating more efficient computer parts,” he said. “This experience has helped me understand how research is conducted and has helped me decide what I want to pursue as a career.”

LIZ FULLER Liz participated in an internship program at Johns Hopkins Applied Physics Lab (APL) located in Laurel, Maryland. Her project involves working with magnetic sensors and developing signal processing methods for special operations/ tactical intelligence missions in the military. When asked about her experience, Liz said, “The project is amazing. I feel like I’m being challenged in a way that forces me to apply my physics background to very important physical problems. The best part is that I’ve been wanting to find an internship that was at a crossroads between physics and engineering, and this is exactly it. The lab works on everything from new horizons to homeland protection, there are truly no limits and I’m already interested in working full time here after I graduate.”

ANDREW HECKLER RECEIVES OHIO STATE ALUMNI AWARD FOR DISTINGUISHED TEACHING

CHRIS HIRATA RECEIVES AN “OSCAR OF SCIENCE”

The Alumni Award for Distinguished Teaching recognizes a maximum of ten faculty members annually for their teaching excellence. A committee of students, previous recipients and alumni choose the recipients from those nominated. Recipients are recognized with a $5,000 honorarium made possible by gifts from The Ohio State Univesity Alumini Association, University Advancement and the Office of Academic Affairs. In addition, the Office of Academic Affairs awards an increase of $1,200 to each recipient’s base salary. Members are also inducted into the Academy of Teaching. Professor Heckler joins a long line of physics professors who have been honored for their distinguished teaching.

Professor Chris Hirata was awarded one of the “Oscars of Science” in 2018 at a star-studded event televised on the National Geographic Channel in a program hosted by Morgan Freeman. He received the New Horizons in Physics Prize “for fundamental contributions to understanding the physics of early galaxy formation and to sharpening and applying the most powerful tools of precision cosmology,” according to the awarders of the annual Breakthrough Prize. The New Horizons in Physics Prize is awarded to promising early-career researchers who have already produced important work in fundamental physics.

PHYSICS.OSU.EDU

FACULTY AWARDS, HONORS AND PROMOTIONS AMY CONNOLLY NAMED 2019 AMERICAN PHYSICAL SOCIETY FELLOW

JAMES BEATTY ELECTED TO THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE

Professor Jim Beatty was awarded the distinction of fellow by the American Association for the Advancement of Science (AAAS) in 2017. The citation accompanying his award reads “For distinguished contributions to experimental particle astrophysics, particularly studies of ultrahigh energy cosmic rays, neutrinos, and antiparticles, and for distinguished service as an academic leader.” The tradition of AAAS Fellows dates to 1874 and comprises and illustrious group of scientists including Thomas Edison, Margaret Mead and James Watson, among many others.

CHUN NING (JEANIE) LAU AND JONATHAN PELZ NAMED 2017 AMERICAN PHYSICAL SOCIETY FELLOWS

The criterion for election is exceptional contributions to the physics enterprise, e.g., outstanding physics research, important applications of physics, leadership in or service to physics, or significant contributions to physics education. Chun Ning (Jeanie) Lau is a professor in the condensed matter experiment group. Her citation was for pioneering advances in the study of graphene and 2D materials, especially in the areas of quantum transport, thermal properties, and the investigation of novel phases. Jon Pelz is a professor in the condensed matter experiment group and is the vice chair for graduate studies and research. His citation was for national leadership in improving graduate education including developing and promoting bridge program components that mentor and support talented students toward doctoral physics degrees who might not otherwise gain acceptance into traditional programs.

ULRICH HEINZ AWARDED HUMBOLDT RESEARCH PRIZE

Professor Ulrich Heinz, University Distinguished Professor and Professor of Physics, was awarded the 2018 Humboldt Research Prize by the Alexander von Humboldt Foundation. Per the foundation website, "This award is granted in recognition of a researcher's entire achievements to date to academics whose fundamental discoveries, new theories, or insights have had a significant impact on their own discipline and who are expected to continue producing cutting-edge achievements in the future.” Award winners are invited to take prolonged periods of research in collaboration with colleagues in Germany, thus promoting scientific cooperation between research institutions in both Germany and the United States.

DEPARTMENT OF PHYSICS

COMERT KURAL RECEIVES NSF CAREER AWARD

In 2018, Professor Comert Kural was awarded a National Science Foundation’s Early CAREER Development Award for his research proposal titled “Spatiotemporal Regulation of Clathrin-mediated Endocytosis.” This five-year, $912,000 grant will support his research for understanding the biophysical mechanisms employed by cells to regulate the uptake of membrane-bound macromolecules.

PROMOTIONS

Amy Connolly: Promoted to Full Professor (2019) Ezekiel Johnston-Halperin: Promoted to Full Professor (2019) Linda Carpenter: Promoted to Associate Professor (2018) Comert Kural: Promoted to Associate Professor (2019) Yuanming Lu: Promoted to Associate Professor (2019) Annika Peter: Promoted to Associate Professor (2019)

WELCOME TO NEW FACULTY MEMBERS BRIAN SKINNER Skinner studies theoretical condensed matter physics, where his work deals mostly with system having strong correlations and long-ranged interactions. This motif encompasses a range of problems both classical and quantum, ranging from electron liquids to supercapacitors to human crowds. In recent years he has become interested in topological materials, and in the question of whether they can have electronic, optical, or thermal properties that are not allowed in conventional metals and insulators. He has also worked on the statistical mechanics of quantum entanglement growth. Skinner holds a patent on a novel magnetothermoelectric effect, and frequently collaborates with experimental groups, especially when it involves interesting transport data.

SASHA LANDSMAN Part of the Nobel Prize in Physics in 2018 was awarded for creating highintensity, ultra-short optical pulses, “Extremely small objects and incredibly fast processes now appear in a new light,” reads the award description on the Nobel Prize website. Landsman studies the interaction of matter with such high-intensity, ultra-short laser pulses. Such fast flashes of light are on a time scale of attoseconds (10^(-18) seconds) to femtoseconds (10^(-15) seconds), which is fast enough to capture the motion of bound electrons inside atoms, molecules and solids. The ultimate goal is accurate imaging and control of electron dynamics on the attosecond timescale. This has both practical (i.e. control of chemical reactions, light-wave controlled electronics) and fundamental (real-time observation of quantum mechanical processes) aims.

2019 UNDERGRADUATE RESEARCH POSTER SESSION 23 undergraduate physics and engineering physics majors participated in this summer's 10-week long Physics Undergraduate Research Program.

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IN THE DEPARTMENT

SCARLET LASER FACILITY BECOMES A FOUNDING MEMBER OF LaserNetUS The High Energy Density Physics Scarlet Laser Facility houses one of the nation’s brightest lasers, with a peak power exceeding one hundred times the power-generating capability of the entire United States. It exceeds the brightness of sunlight by a factor of 1022 (10 billion trillion). The Department of Energy Office of Science has decided to have the Scarlet Laser, four other university based lasers, and four lasers at national labs join together in a network called LaserNetUS to support high-power, laser-based science for a broader national community. Scarlet, designed by Enam Chowdhury, an assistant professor in the College of Engineering, is currently funded at $500,000 per year and led by Professor Douglass Schumacher of the Department of Physics.

IN MEMORIAM Professor Chen-Ping (Alfred) Yang passed away at age 87 on May 1, 2018, in Columbus, Ohio. Chen-Ping was born on Nov. 17, 1930, in Beijing, China, and spent his youth in Kunming, Yunnan, China. Chen-Ping loved learning and teaching — he came to the United States in 1948 to attend Brown University (BA 1952), continued his education at Harvard University (MS 1953), and completed his PhD at the Johns Hopkins University in 1960. For 37 years, he taught physics at The Ohio State University until his retirement in 1998. Memorial donations may be made to the American Cancer Society. Arthur Joseph Epstein, Ohio State University Distinguished Professor of Physics and Chemistry, died on August 25, 2018, in Columbus, Ohio, at the age of 74. Professor Epstein co-discovered the first magnet based on organic materials in 1985 and was recognized as the world’s leading expert in how polymers conduct electricity. In addition to his research accomplishments, Professor Epstein was a principal organizer and 14-year director of Ohio State’s Center for Materials Research (CMR). Professor Epstein was a Distinguished University Professor at Ohio State, a Fellow of the American Academy for the Advancement of Sciences, a member of the American Physical Society and the American Chemical Society and was editor-in-chief of the Journal of Synthetic Metals. He helped found several companies based on his group’s research including Eeonyx Corp and Traycer and served as a consultant for DuPont, Xerox, Honda and Mitsubishi. Memorial donations may be made to Arthur J. Epstein Distinguished Emeritus Professor Graduate Endowed Travel Fund. 18

DEPARTMENT OF PHYSICS

PHYSICS BY THE NUMBERS 59 FACULTY

48 STAFF

50 POSTDOCS & RESEARCH

20 (administrative) 6 (research & facility) 22 (instructional)

SCIENTISTS

STUDENTS WITH 200+ GRADUATE ABOUT 30-40 PHDS EACH YEAR

MAJORS WITH 500+ UNDERGRADUATE ABOUT 70 BS DEGREES EACH YEAR

UNDERGRADUATES PARTICIPATE 70% OF IN RESEARCH OR INTERNSHIPS

5 ENDOWED FACULTY

POSITIONS

$11M IN ENDOWMENTS

AWARDS: 1 RHODES SCHOLAR 1 MARSHALL SCHOLAR 2 CHURCHILL SCHOLARS 5 FULBRIGHT SCHOLARS 21 GOLDWATER SCHOLARS 19 NSF GRADUATE FELLOWS 29 AMERICAN PHYSICAL SOCIETY FELLOWS 8 AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE FELLOWS 1 NEW HORIZONS PRIZE 1 ONSAGER PRIZE

SUPPORT OUR DEPARTMENT Your support is critical to the Department of Physics’ continuing success. From scholarships to teaching awards, to student travel and research support, your donation will make a tangible difference in the lives of the students and faculty in our department. All gifts are tax deductible as permitted by law. Please consider a gift to the Department of Physics. DISTINGUISHED POSTDOC LECTURE FUND Fund #316741 The department has established a new Distinguished Postdoc Lecture Series, which will begin in the spring of 2020. The series will be used to recognize promising young scholars in physics. The program will bring these individuals to campus for a lecture about their research. During their visit, the honorees will have an opportunity to visit with other postdocs, faculty and students in the department. The program seeks to establish and foster collaborations with emerging future leaders in the field. GRADUATE PHYSICS FELLOWSHIP FUND Fund #302347 Fellowships are key to attracting the very best students. UNDERGRADUATE PHYSICS RESEARCH ENDOWMENT FUND Fund #607394 Income provides undergraduate scholarship support for one or more students.

1 SCHAWLOW PRIZE 9 UNIVERSITY DISTINGUISHED SCHOLARS OR PROFESSORS

PHYSICS CHAIRMAN’S DISCRETIONARY FUND Fund #302325

14 UNIVERSITY DISTINGUISHED TEACHING AWARDS

Provides the chair with the flexibility to fund small but urgent academic and research priorities as well as the ability to host important community building events within the department.

28 FACULTY HAVING WON YOUNG INVESTIGATOR AWARDS

PHOTO CREDITS IN MAGAZINE PAGE 2: RICK LEONARD PAGES 5, 16, 17, 19 AND BACK COVER: LINDSEY THALER PAGE 7: ROBB MCCORMICK PAGES 8 AND 9: JOSH FRIESEN

For questions or to learn about other opportunities for support, please contact the Arts and Sciences Advancement Office at ascadvancement@osu.edu or 614-292-9200. To make your gift online, visit osu.edu/giving. PHYSICS.OSU.EDU

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DEPARTMENT OF PHYSICS