Interview with  Gérard Mourou on 6 December 2018 during the Nobel Week in Stockholm, Sweden.

Gérard Mourou: I am Gérard Mourou. I’m from France and my field is lasers.

What are the benefits of working in an international setting?

Gérard Mourou: I think that I always believed that science should be used to unify people and I’m a strong believer in this and it’s like music and everybody speaks the same language and science is the same thing. In science we all speak the same language and we work on the same problems and we try to make this world better.

Where does your passion for science come from?

Gérard Mourou: The passion of lights, in fact, comes from the laser. The first time I’ve seen the lasers, I said “Wow”, I couldn’t believe, to see this light, so well behaved, this beam of light, with pure colours. That was direct captivating for me and kept me ongoing for 45 years.

How did it feel to discover you had been awarded the Nobel Prize?

Gérard Mourou: Of course the culmination of a career as a physicist is winning the Nobel Prize and then when you get this phone call from Stockholm … I knew of course that the Nobel Prize for Physics is always given on the first Tuesday of October and before noon. And I was kind of waiting, even if I had a small chance, waiting and also interested to know who was going to get it. But anyway I’m a harried swimmer, so I was on my way to go to the swimming pool and my secretary just waved at me and said “Gérard, could you come back. We have a phone call for you from Sweden, from Stockholm”. Oh, wow /---/, and so I picked up the phone and of course it was coming from Stockholm and so I almost crashed because it’s dynamite [laughing] when you hear it and that change your life also.

How relevant has persistence been to your career?

Gérard Mourou: Oh, this has been extremely relevant. One thing I’ve done … we have invented a new type of laser with Donna Strickland, my co-laureate and student. We invented the lasers and in a process of aligning the laser my student, not Donna, but another student, got the beam in his eye, and so we took the student … he was not wearing goggles like he was supposed to, but accidents happen and so we took him to the hospital where is an ophthalmologist. The ophthalmologist looked in his eyes, his retina and so on and he said: “Hm, yeah, you got the laser in your eye, in your retina. Your retina is burned.” but he said: ”What type of laser is it?” and the student told him it was a new type of laser, he said, and he asked him “Why are you asking these questions?” “Well, because the damage you have in your eye is perfect”. And that started what now is femtosecond ophthalmology. There is millions of people now using the femtosecond laser for surgery. So it was really clearly a mistake. It was not planned at all. That opened up a completely new field and you have millions of people who are benefitting from this application now.

Are environmental issues close to your heart?

Gérard Mourou: This is very close to my heart. All the environmental issues, I will say, is on the top of my preoccupations because we see every day of course that science brings a lot of goffe technology, brings technology on, but now it is science. We invented in fact a new terms for this type of science, should be ‘toilet science’, do you understand, ‘toilet science’, because some of the science help to destroy the planet with all the technology that came out of that, so we should really now think about really cleaning the mess, basically, which has been done, we have to say that as a consequence of this new science and technology.

What responsibilities do scientists have to the environment?

Gérard Mourou: I would say yes, we have to be very careful about what we do. I think it’s of course … you have sciences then you have engineers and technologies and then you have products and consumers and so on. I think for scientists we really need to discover work on improving cleaning the planet for instance in nuclear power we have always nuclear waste. We are working with lasers on trying to basically improve the situations because nuclear energy is certainly a very important source of energy which could be very clean at one conditions, we have to clean up the waste after that. If we come up with reasonable solutions to clean up this waste, then that will be a fantastic improvement.

What is the scope for future applications of lasers?

Gérard Mourou.: The scope for our lasers is enormous, it’s enormous. In 1960 the laser was demonstrated by Ted Maiman but it was invented by Townes and as soon as the laser was invented people were saying “What’s going to be the use of this laser?” So they tried to find applications for the lasers, they tried to find applications In fact when we also demonstrated the very ultra-high intensity lasers that we got the prize for, also we weren’t sure about the applications and now we have of course enormous amount of applications. And what I like, of course, is applications in the medical, in medicines and so on. It’s very important. It’s on the top of my agenda.

What is your advice for young scientists?

Gérard Mourou: I think I have only one advice for students who would really like to get into science and researching on that. You have to be passionate. If you don’t, if you are not passionate about it, you should do something else. It has to come from the heart of you because it’s very hard. It’s very hard for you but also, I have to say, for the family because you are always thinking about your research, because you are passionate. So you are thinking only about one thing and so sometimes it’s tough for the people who are with you.

Besides passion, what are the qualities top scientists need to have?

Gérard Mourou: I mean the type of quality you need, of course, is the ability to endure being long time in the lab and be patient and obstinate. You have to be focused.

What do you do in your spare time?

Gérard Mourou: My swimming is very important. I’m swimming. Well, I’m a skier. I was born in the French Alps. This town was named Albertville and where we have the Olympic Games and so skiing is basically a natural thing for me but also I love swimming. Swimming for me is like yoga, it’s very peaceful. I’m talking about open water swimming, and I love that.

When swimming, you aren’t thinking about your research?

Gérard Mourou: That’s right and I have a problem because, when I think about this, I’m in a state when I’m swimming. You are totally relaxed but also you are thinking about your research and that’s a problem because some time I forget the number of laps I’m doing.

Who inspired you in the beginning of your journey?

Gérard Mourou: Because my dad was working in an electrical power company in the Alps, the French Alps, so we were always talking about current, power, amperes, voltage and things like transformers and all that because this is what he was doing and he was always explaining to me how these were working … with my dad, playing chess and doing, I mean learning about physics, yes.

What do you enjoy about working with graduate students?

Gérard Mourou: Working with graduate students is like with your family, being with really your family. I mean that’s a way I always treated my students. We stay in the labs together, we discuss in the lab, weekends we spend together and so on, I mean, always thinking about what we want to achieve and that brings the students and the faculty together and we are aging, the faculty is aging, but we’re renewed, our students are renewed, so we are always close to the very young students and I’m very pleased also that many of my students, a few, well many, about ten will be attending the Nobel Lecture and the events.

How has your research been applied over the years?

Gérard Mourou: Since the very beginning I was very attracted by trying to really produce very, very short pulses. In the beginning it was the picosecond and then femtosecond and then attosecond and so on. So picosecond is 10^-12 so it’s one thousandth of a billionth of a second and a femtosecond is a billionth of a millionth of a second. And I was always fascinated by what you could do because we could really, for the first time, we could see things moving in these time scales and of course we are not moving in these time scales, but molecules, atoms, electrons and all that, they move in this time scale and of course your eye is too slow to follow them. So trying to understand the world with this new tool, this tool of having very short pulses so you can track down the evolutions of very small systems to understand reactions and that, this is really extremely fascinating.

Then came the second application and the second application. If you are producing these very, very short pulses, then you can produce, if you are smart, very high intensity, very high peak power, and this is where we had a problem, with Donna, is a fact, because the pulses are short, the power that you are trying to get, can be very high, but at one point you are breaking down the laser because the power, the peak power is too high. And that’s of a clamp down the laser power that you can produce and it’s where we came up, with Donna, with this idea of CPA which is chirped pulse amplification, which could circumvent these problems of the laser being destroyed as we were amplifying the pulse and getting more peak power.

Can you summarise your discovery in 30 seconds?

Gérard Mourou: My Nobel Prize was awarded because of my work with laser, with very, very short pulse laser, and why do you want to have very short pulse lasers? It is because these pulses will be also important for communications, very important for communication in general, very important also in the medical world, very important for many other disciplines. Because with these very short pulses you will be able really to observe or to track down reactions which happen in cells, but also which may happen also in a transistor for instance for communication, fast electronics and so on and also because this very short pulse gives you viability to produce, over a very short time, extremely high peak power so you can use that for nuclear physics and maybe also trying to understand events which are happening in the cosmos. Because you can really produce the highest temperature, the highest pressure, the highest field, the highest gravity, so you can really simulate and bring back into the lab what is happening in the cosmos and in life in general.

Watch the interview

Did you find any typos in this text? We would appreciate your assistance in identifying any errors and to let us know. Thank you for taking the time to report the errors by sending us an e-mail.