Ursula Keller is a physicist recognized for her work in ultrafast laser physics and attosecond science. She is known particularly for her pioneering contributions with the development of ultrashort pulsed lasers, the study of fundamental modelocking physics and pulse formation, the invention of techniques for frequency comb generation and stabilization, and groundbreaking studies of the physics of light-matter interactions on attosecond timescales. For example she invented the semiconductor saturable absorber mirror (SESAM) which solved a 25-year-old challenge and the attoclock. She has been a tenured professor of physics at ETH Zurich since 1993, and also a director of the Swiss multi-institute NCCR MUST program in ultrafast science since 2010. She received the Ph.D. from Stanford University in 1989 and the Physics “Diplom” from ETH in 1984 with top-ranked results. She was a Member of Technical Staff (MTS) at AT&T Bell Laboratories from 1989 to 1993, a ?Visiting Miller Professor? at UC Berkeley 2006 and a visiting professor at the Lund Institute of Technologies 2001. She has been a co-founder and board member for Time-Bandwidth Products (acquired by JDSU in 2014) and for a venture capital funded telecom company GigaTera (acquired by Time-Bandwidth in 2003). She is the founding president of the ETH Women Professors Forum.

Research Interests

Ursula Keller continues to push the performance and the industrial know-how transfer of ultrafast lasers in many key dimensions (shorter pulses, more power, higher repetition rate, new types and wavelengths of lasers) in many cases by orders of magnitude. For example today, most ultrashort industrial lasers are based on her SESAM modelocking technique. Furthermore she continues to pioneer novel semiconductor lasers, dual-comb modelocking, a paradigm shift in frequency metrology and is working towards the mid-infrared regime. Her cutting edge few-cycle pulse generation with carrier envelope offset (CEO) phase stabilization enabled the invention of the attoclock to measure a finite electron tunneling time. Work is ongoing addressing this unresolved fundamental question and debate in quantum mechanics. The frontier laser research with the CEO phase stabilization also enables petahertz electronics, as the magnetic field interaction can be neglected within the dipole approximation. The goal is a better understanding of the underlying ultrafast dynamics in atoms, molecules and condensed matter physics with a systematic examination and a potential exploitation of the non-equilibrium behaviour of quantum systems on the fundamental electron time-scale in the attosecond regime. The attosecond time scale becomes important for next-generation integrated circuits, novel concepts in artificial photosynthesis and light-induced carrier separation with a potential impacts to the fields ranging from energy to bio-medicine.

Membership Type

International Member

Election Year


Primary Section

Section 31: Engineering Sciences

Secondary Section

Section 33: Applied Physical Sciences