Interview transcript

Professor, very nice to meet you. It has been a few years since you received the Nobel Prize in 1973.

Leo Esaki: That’s right.

I would like to start off by asking you what made you interested in physics at the very beginning. Why did you choose that subject?

Leo Esaki: When I was at high school I had the opportunity of what kind of field I should go into. This is during the war. Distraction, Japanese suffer of that. I was at high school and university. At that time I liked to get fundamental knowledge in that circumstance and I wanted more basic knowledge in the natural science, physics certainly most fundamental. If you know physics I think you can do many other things. During the psychology of war you like to know – before you die – to understand the most fundamental things.

Did you want to be part of rebuilding Japan?

Leo Esaki: This is after the war. I entered university in 1944 and I graduated university -47. The war ended in -45. I entered Tokyo Imperial University and after the war when I graduated just Tokyo University. After I graduated Japan was in a bad situation. Everything was destructed and Japanese industry business was in poor condition. I could have stayed at the university to study, but I decided to go into industry.

Was it better for you to go into industry rather than stay on at university?

Leo Esaki: I thought I could contribute to the Japanese industry because the Japanese economy and industry were so bad so this was my prime motivation to go into industry.

You made your major discovery in 1957 which then you were awarded the Nobel Prize for, that was at Sony. After that you moved to the United States. Was that a difficult transition for you, to go from Japan to the United States in 1957 or -60?

Leo Esaki: What do you mean difficult? It was easy because I got many offers from the United States, in that aspect very easy, I just accepted one. Of course culture is very different between Japan and the United States so that made it slightly difficult. Way of thinking and how you do many things different. Sort of a cultural shock for me to move from Japan to the United States. But science is a more international enterprise, it’s a global enterprise. As a scientist I don’t think it was much of a problem. It was more problems of daily life, a different lifestyle. Even the language English – Japanese to English is a big difference – so that created some problems of course.

After two years I decided to stay in the United States, but I had a call from Japan, so I had another culture shock – from United States to go back to Japan. In the United States I worked in industry. As I mentioned, after graduating my university I entered Japanese industry, I changed from American industry, but I got an offer from Japan, I was called from the President of the National University. I went from scientist in a private industry to educator at this national university. The culture shock once again, United States to Japan, industrial researcher to government educator.

I would like to come back to your move going back from United States to Japan just in a moment, but to stay in the United States for a little bit longer: you were working at IBM, what was it there that you found useful working the industry over those years? You said as a scientist it wasn’t difficult, but daily life was a shock. As a scientist at IBM, what culture did you find there that was creative for a scientist of your status?

Leo Esaki: I joined IBM in 1960 and then after a few years I was elected IBM Fellow. Being a Fellow is I was given freedom, suddenly. More obligation to the company but I could do anything I wanted, so I got the idea to make a man-made quantum structure. Superlattices is one of the man-made quantum structures. I’m a material scientist and usually you study many materials, but I got the idea that I’d like to create material, I like to design, I like to engineer man-made materials. This is a new avenue of material science. We like to make man-made material that doesn’t exist in nature. These synthesized new materials had totally new properties. The materials – usually God gave these materials to us – gold and silver. God gives us creativity so I can make and create materials which God never gives us. The new materials had very many interesting properties, we started those programmes. In material science somebody has to prepare the materials. Somebody has to make the measurements – this is not one man’s effort. I organised a group, not a very big group, about ten people, to work with me. This is the basic research, not very committed.

Can I come back to when you moved back from the United States to Japan, you said it was a culture shock. What were the biggest difficulties at that time? Was there something you wanted to bring with you from America that was difficult to implement in Japan?

Leo Esaki: That the culture is very different between Japan and the United States is one thing, but the other is that in the United States I was a researcher, but in Japan I’m President of that university which is more an educator. For scientists, you need more creative minds. For an educator, you need a judicious mind because it’s a national university. You’re a bureaucrat, a government officer.

Do you miss that part of the creativeness as a researcher when you had to go back and be more of an educator?

Leo Esaki: I think I missed the research, I missed that direct contact of that activities.

Is there also a difference in the hierarchical structure within the research departments if you compare between the United States and Japan? Has the Japanese a more hierarchical structure and in which way could that either enhance or diminish creativity?

Leo Esaki: United States is more bottom-up kind of activity for research but Japan is generally top down, so that’s slightly different. But certainly in Japan that is changing very fast now to give more opportunities to young scientists and young people, to be more encouraged and creative. History tells us to progress science you need two things. One is individual creativity, the other is the dynamic interaction among scientists. That dynamic interaction is very active in the United States, so that’s one of the progresses for the United States’ scientists, very easy dynamic interactions – more open with things. Of course individual creativity is more fundamental, necessarily.

My last question, Professor, would be: what is out there to discover? What is your biggest question mark? If you had a wish list, what would you ask somebody or what is the big discovery to be done in physics?

Leo Esaki: We still need a breakthrough in many ideas. Communication, computer fields. One breakthrough we can expect is quantum computers and quantum telecommunications, using the principle of quantum mechanics. Quantum mechanics – already in the 20th century that was formulated, quantum mechanics implemented many things, but the 21st century we will use principle of quantum mechanics, there is one principle of the super position, the super position principle. If you use those principles, you can make quantum computers which is a vast improvement of the present computers. If you use that quantum communication you can use the cryptography. You cannot decode your code, you could make very safe communication. I think that’s one of the fields which is a big project of the Japanese government in quantum telecommunications, and I’m organising these activities. We need individual creativity to make these kinds of things, I think this is one of the important things. The communication is very important to everybody. Everybody has a portable phone and a PC, and we still need improvement in those fields.

Improvement and faster.

Leo Esaki: Using quantum mechanics for these applications.

That will be very exciting to see when that is happening. Thank you very much Professor for your time.

Leo Esaki: Very good.

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