ME Professor Xiang Zhang's PhD student Zi Jing Wong, has won the Best Student Paper award at the 2015 SPIE Active Photonic Materials Conference. Wong's award winning paper, "Single Mode Parity-Time Laser," discusses:
"The concept of parity-time (PT) symmetry exploits the interplay between the material loss and gain to attain novel optical phenomena such as exceptional point and unidirectional light propagation. Here we experimentally demonstrate a PT symmetry breaking laser that allows unique control of the resonant modes. In contrast to conventional ring cavity lasers with multiple competing modes, our on-chip InGaAsP/InP based PT microring laser exhibits intrinsic single-mode lasing regardless of the gain spectral bandwidth. Thresholdless parity-time symmetry breaking due to the rotationally symmetric structure leads to stable single-mode operation with the selective whispering gallery mode order."
Congratulations, Zi Jing!