Beecroft Building, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU
Dr Ryan Hamerley, NTT PHI Laboratories
Abstract
Significant progress has been made towards high-performance, nonlinear nanophotonics through engineering the Q-factor and volume of photonic cavities. But waveguided optical systems also possess a temporal dimension whose control is often neglected. This talk gives two examples of how engineering the temporal properties of light in nonlinear resonators can enable new phenomena and break the conventional tradeoffs associated with single-mode optics. (1) First, I introduce the concept of temporal trapping in ring resonators, where cross-phase modulation (XPM) and group-velocity dispersion counteract to form trapped states, “flying cavities” that confine the light along the resonator’s axial dimension, reducing the effective mode volume (and thus increasing the effective nonlinearity) by orders of magnitude. Numerical models confirm the possibility of high-fidelity χ(2) quantum gates, circumvent-ting the Shapiro no-go result on pulsed quantum nonlinear optics, and with order-of-magnitude calculations, we show a reasonable path to achieving room-temperature strong coupling g/κ > 1 in LiNbO3 resonators. (2) Next, I discuss the new opportunities χ(2) poses for lightsource development and introduce the quadrature-amplitude-modulated (QAM) OPO, a new type of frequency comb that simultaneously achieves stable turn-key operation, high efficiency, flat spectrum, broad dispersion-limited bandwidth, and rapid (electro-optic) tunability.
Bio
Ryan Hamerly was born in San Antonio, Texas in 1988. In 2016 he received a Ph.D. degree in applied physics from Stanford University, California, for work with Prof. Hideo Mabuchi on quantum control, nanophotonics, and nonlinear optics. In 2017 he was at the National Institute of Informatics, Tokyo, Japan, working with Prof. Yoshihisa Yamamoto on quantum annealing and optical computing concepts, and is currently a Senior Scientist at NTT PHI Laboratories and a visiting scientist at MIT, Cambridge, Massachusetts, with Prof. Dirk Englund.