Invitation to a talk by

Mordechai (Moti) Segev

Technion - Israel Institute of Technology

Photonic Time-Crystals and Light-Matter Interactions Therein

Photonic Time Crystals (PTCs) are dielectric media whose refractive index is strongly modulated periodically in time, at time scales shorter than a single optical cycle. These systems conserve momentum but not energy, and are characterized by momentum bands separated by band-gaps where the amplitudes of their eigenmodes can increase or decrease exponentially.
The fundamentals of PTCs will be introduced along with the classical and quantum features of light-matter interactions in PTCs. Among these, the most notable is the emission of light in PTCs, which opens new avenues for making widely tunable lasers that do not rely on any atomic resonance and draw their energy from the temporal modulation of the medium. Another important feature is the quantum aspects, which yield a plethora of fundamental features ranging from the generation of pairs of entangled photons, controlling spontaneous emission through the temporal modulation, and creating 2D cluster states. 
Finally, the experimental progress on order-unity modulation of the refractive index faster than a single cycle will be presented, focusing on the recent breakthrough of observing time-reflection at optical frequencies. Last but not least, nonlinear optics in such time-varying media will be discussed, envisioning new mechanism for high harmonic generation in solids. 

About Prof. Segev

Moti Segev is the Robert J. Shillman Distinguished Professor of Physics and Electrical Engineering, at the Technion, Israel. He received his BSc and PhD from the Technion in 1985 and 1990. After postdoc at Caltech, he joined Princeton University as Assistant Professor (1994), becoming Associate Professor in 1997, and Professor in 1999. Subsequently, Moti went back to Israel, and in 2009 was appointed as Distinguished Professor.  
Moti's interests are mainly in photonics, solitons, lasers, and quantum optics. He won numerous international awards, among them the 2007 Quantum Electronics Prize of the European Physics Society, the 2009 Max Born Award of the Optical Society of America, and the 2014 Arthur Schawlow Prize of the American Physical Society. In 2011, he was elected to the Israel Academy of Sciences, in 2015 to the National Academy of Science (USA), and in 2021 to the American Academy of Arts and Sciences (AAAS). In 2014 Moti Segev won the Israel Prize (highest honor in Israel) in Physics, in 2019 he has won the EMET Prize in Physics, and in 2024 he won the Rothschild Prize in Physics. In 2020 he was elected to be the Neil Armstrong Distinguished Visiting Professor at Purdue University, and in 2023 he won an Honorary PhD from the University of Quebec.  
However, above all his personal achievements, Moti takes pride in the success of his graduate students and postdocs, among them are currently 27 professors in the USA, Germany, Taiwan, Croatia, Italy, India, China, Switzerland and Israel, and many holding senior R&D positions in the industry.

Date
Thursday, 03.09.2026 | 11:30

Location
Ernst Mach lecture hall
Faculty of Physics

Hosted by 
Philip Walther