Laser Focus

HER VOICE

Nobel Prize winner Dr Donna Strickland discusses her pathway to physics.

Words Joanna Chiu

University of Waterloo

Last October, Canadian Dr Donna Strickland became the first woman in 55 years to win the Nobel Prize in Physics. Before her, the award has gone to just two other female laureates in the field: Maria Goeppert-Mayer in 1963 for her discovery of the nuclear shell model; and Marie Curie in 1903, along with her husband, for their work on radioactivity.

Strickland, who is a professor of physics at the University of Waterloo in Canada, shared the prize with French scientist Gérard Mourou, whom she had worked with at the University of Rochester, New York, for the invention of “chirped pulse amplification” (CPA), a technique for generating high-intensity short-pulse lasers.

Since its invention in the mid-1980s, CPA has led to the proliferation of a number of laser-based tools and has allowed doctors to perform millions of corrective laser eye surgeries every year. Before its conception, the medical use of lasers was limited because longer pulses generated heat that was dangerous to human tissue.

We speak with Strickland about her journey, the scientific breakthrough and how her work could eventually enable new cancer treatments.

ARIANA: What has it been like for you since winning the Nobel, and how do you think the win will impact your work?

DR DONNA STRICKLAND: Winning was a complete surprise. My calendar is filling up with invitations to speak. The Swedish embassy invited me for a dinner, and my own parliament is going to honour me. I had dinner with the Swedish king [Carl XVI Gustaf]. It’s quite a different life with this prize! It’s been busy, but hopefully I can find some time for my research. I want to develop new types of lasers so hopefully [the recognition] will bring more opportunities, funding and new collaborations.

A: You jokingly call yourself a “laser jock” in interviews. How did you get into the field?

DS: Why lasers? It’s something that goes back to my childhood. When I was younger, my parents brought the family to the Ontario Science Centre, and my dad pointed to a big laser on display. He said lasers would be the way of the future. Back in the 70s, it’s not like you saw lasers around often. We didn’t have laser pointers or checkout scanners at grocery stores. Lasers were a research tool.

When [years later] I had to decide where to go for my undergraduate education, I looked through local universities and saw that McMaster [a public research university in Hamilton, Ontario] had a programme called Engineering Physics. It had four areas – including one about lasers – and I thought that seemed fun. The moment I read “lasers”, I had a gut reaction that it would be a good fit for me.

A: When did you start working on short-pulse lasers?

DS: While studying my PhD at the University of Rochester, I met Gérard Mourou [co-recipient of the Nobel Prize] and we started working together on lasers with short pulses – the project that would eventually lead to the Nobel. The ‘short pulse’ means the laser isn’t on for a long time, so you’re not heating materials [such as human tissue] up which can cause complications.

A: Could these lasers play a role in cancer treatments in the future?

DS: Yes, there is cancer treatment research looking at the possible applications of these lasers. The energy of lasers currently used in hospitals is not high enough to penetrate parts of the body, so we will need to get higher energy beams to do that. It’s still in the proposal stage and there’s a lot of research to be done. If they succeed, that could lead to radiation treatments that aren’t possible now, for instance to treat brain cancer.

A: Did you ever have any career setbacks?

DS: Well, I would say that one career setback occurred after my post-doc. I turned down offers to join the faculty of [different universities] because the man I wanted to marry [now husband Douglas Dykaar, a researcher] lived and worked in New Jersey. [In the intervening years], he’s followed me and took a job so that we could be together. So we’ve both taken turns putting family ahead of our careers.

A: Why do you think it took so long for another woman to win the Nobel Prize in Physics?

DS: Over the years there has been bias, but the [Nobel] committee knows that there are women out there who are doing top-notch research. The thing that’s been happening in the last 15 years is that slowly people are becoming aware of bias and things are changing.

I think every field of work – period – has to be open to everybody."

– Dr Strickland

Dr Strickland in her laboratory

University of Waterloo

A: Why is fighting discrimination so important?

DS: I think every field of work – period – has to be open to everybody. We need to encourage everybody to figure out for themselves what they’re good at and encourage them to do it. Otherwise, we’re not using the resources we have on hand.

The interview has been condensed for clarity.

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