Speaker: Dr. LU Xiyuan, Univeristy of Maryland
Time：Friday,9:30-10:30 a.m.,15th November
Sponsor：Prof. LIANG Wei
Recent advances in nanophotonic technology have led to major progress and new promise in wideband nonlinear optics. In this talk, I will discuss our recent efforts in exploring nonlinear nanophotonics across widely separated spectral bands from visible (~650 nm) to telecom (~1550 nm), for both classical and quantum applications. In the classical regime, efficient spectral translation of light is useful for many integrated photonics applications, including spectroscopy, sensing, and metrology, where coherent visible light needs to be generated efficiently on-chip. I will introduce our recent work1 on how to translate telecom light into the visible band by stimulated four-wave mixing, a third-order nonlinear optical process, inside a high quality factor silicon nitride microring. The translation efficiency is comparable to the best current second-order nonlinear result and is a record-high value for nanophotonic spectral translation. In the quantum regime, narrow-linewidth, wide-band quantum entanglement is particularly useful in connecting different species of trapped atoms/ions, defect centers and quantum dots to the telecommunications bands for future quantum communication systems. I will discuss our work2 in generating visible-telecom photon pairs with record-high brightness and efficiency. Time-energy entanglement is generated and then distributed over a 20 km fiber. I will also introduce our exciting new progress in both applications areas, including visible-telecom optical parametric oscillation3 and wideband quantum frequency combs.
Xiyuan Lu is a CNST/UMD Postdoctoral Researcher in the Photonics and Plasmonics Group. He received a B.S. in Physics from Nanjing University, China and a Ph.D. in Physics from University of Rochester. His doctoral research focused on entangled photon sources in high-quality silicon microcavities, and on silicon carbide micro/nanophotonic devices for optomechanical and nonlinear optical applications. He is now working with project leader/NIST fellow Kartik Srinivasan in developing chip-scale nonlinear nanophotonic devices for microcavity frequency comb, quantum/classical light generation and conversion, quantum entanglement, and atomic memory.