How did you get started in your field, and what prior research or whose prior work helped to start you on your way?

I was born in Switzerland on June 21, 1959 and grew up in Zug, Switzerland, about 30 km south of Zürich. I graduated from the ETH in 1984 with a diploma degree (similar to a masters) in physics. From late 1984 to 1985, I worked on optical bistability at Heriot-Watt University in Edinburgh, Scotland. Then I moved to Stanford University in Stanford, CA and earned my M.S. and Ph.D. degrees in Applied Physics in 1987 and 1989, respectively. My doctoral thesis was done under the supervision of Prof. Dave Bloom, investigating optical charge and voltage probing of GaAs integrated circuits. For my first year at Stanford I held a Fulbright Fellowship and for the following year I was an IBM Predoctoral Fellow. I very much enjoyed my time at the Ginzton Lab and developed many good friendships there. I was also encouraged by Dave Bloom, Bob Byer, Steve Harris, Geraldine Kenney Wallace (a visiting professor from Toronto), and many others to give my best and excel beyond my own expectations. Looking back, I see this experience as a key event in my achievements since then. I was also fortunate that Dave Auston (at that time still at Bell Labs) made it possible for me to become a summer student at Bell Labs in 1996. This was also a perfect excuse to drive across the U.S. (twice) in an old station wagon (which of course also broke down at least twice).

In 1989, I became a Member of Technical Staff (MTS) at AT&T Bell Laboratories in Holmdel, New Jersey. Having had a great Bell Labs experience as a summer student, this was basically my dream job. It also put me right in the midst of the challenges for dual-career couples, as my new spouse and I decided to maintain a bi-coastal marriage. Living apart had the advantage that there was plenty of time for research, and also afforded the opportunity for many adventurous rendezvous around the USA and the world. At Bell Labs, I conducted research on photonic switching, ultrafast laser systems, and semiconductor spectroscopy. During this time I also started my work on semiconductor saturable absorber mirrors (SESAMs) to passively mode-lock solid-state lasers. Previous attempts to passively mode-lock diode-pumped solid-state lasers resulted in Q-switching instabilities, which at best produced stable mode-locked pulses within longer Q-switched macropulses (i.e. Q-switched mode-locking). The SESAM device was a breakthrough resulting in the first demonstration of self-starting and stable passive mode-locking of diode-pumped solid-state lasers with an intracavity saturable absorber in 1992 (Optics Lett. 17[7]:505-7, 1 April 1992).

In March 1993 I was appointed an Associate Professor and in October 1997 I became a Full Professor in the Physics Department at the Swiss Federal Institute of Technology (ETH) in Zürich, Switzerland. My current research interests are in ultrafast lasers, attosecond science, spectroscopy, local probes and novel devices for applications in optical information processing, communication, and medicine. Together with my research team at ETH we have continued to push the frontiers in passively mode-locked and Q-switched solid-state lasers in terms of pulse duration (demonstrated shortest pulses directly from a laser oscillator—Optics Lett., 24[9]:631-3, 1 May 2000—and demonstrated shortest pulses from a Q-switched solid-state laser—J. Opt. Soc. Am. B, 16[3]:376-88, March 2000), average output power (27 W picosecond and 16 W femtosecond diode-pumped solid-solid state lasers—Appl. Phys. B, 71:19-25, 2000 and Optics Lett., 25[11]:859-61, 1 June 2000), pulse repetition rates (up to about 60 GHz passively mode-locked Nd:YVO4 lasers—Appl. Phys. Lett., to be published 12 October 2000—and more recently up to 77 GHz—Electronics Lett., in progress). Key for this success was a systematic research effort to understand the underlying physics and scaling issues.

  What would you rate as your most difficult or trying professional moment?

The pressure for success in the academic world has become so severe that sometimes ethical standards start to crumble. World-record results, for example the shortest laser pulse, draw a lot of attention and also result in a high citation index. But how far do you want to go for a world-record result? I was pretty amazed to see first-hand what competing groups are willing to do to be first. Is it O.K. to reference prior work not at all or out of context to give the impression of being first? When I started life in the academic world, I was not really aware of these issue.

  Which of your professional achievements brings you the most satisfaction?

Excellent research, a great research team, motivated students, and stimulating research collaborations.

  What impact might your work and research advances in your field have on the general public?

Short laser pulses are being used in many fields that could have a direct positive impact on the quality of life. Certainly the most direct one would be medical procedures and diagnostics. Short pulse lasers are being used to detect cancer cells, measure bio-chemical events, image live cells and organisms, investigate genetic issues, perform advanced surgical procedures in the eye, brain, and other areas. My dream would be an ultrafast laser that would cure the common cold, but that is still pretty far in the future.

On a more industrial level, ultrafast lasers are being used in chemical and semiconductor measurement instruments, digital project displays, and of course in the increasing push for ultra-high-speed bandwidth fiber transmission systems. Basically all of these help advance the bandwidth revolution which we are in the middle of currently.

In the big picture ultrafast lasers are an important tool to measure phenomena which are happening at the borders of our perception. This leads in general to new discoveries and new understanding of how things work—the basic goal of physics.

  Did you expect your work to become highly cited, or is this surprising to you?

I knew that my citation index is above average, but I was surprised to hear that the ISI analysis places me among the top 5 most-cited researchers publishing in the field of optoelectronics in the past decade.

  What lessons would you draw from your work to pass on to the next generation of researchers?

Do good work, hang in there, play hard, but play fair!

  If you had the power to make a single, sweeping change in the way that scientific research is conducted and presented, what would it be?

Long-term funding support with less bureaucratic requirements. Actually, my dream is to have enough money to fund my own research—so that I can spend most of my time on research and not on general management issues. With good performance—in terms of publications, citation index, etc.—we should have more freedom in our research efforts. Funding agencies should not micromanage good researchers. This actually results in wasted money and time for everybody involved. The worldwide tendency for less support of university research will make the academic career less attractive in the near future—especially with a booming high-tech industry.

  Would you like to leave any other comments about your work or share a personal side of yourself?