3 papers
physics.optics2025
Bi-stability and period-doubling cascade of frequency combs in exceptional-point lasers
Xingwei Gao, Hao He, Weng W. Chow +2
Recent studies have demonstrated that a laser can self-generate frequency combs when tuned near an exceptional point (EP), where two cavity modes coalesce. These EP combs induce pe…
physics.optics2024
Quasinormal coupled-mode analysis of dynamic gain in exceptional-point lasers
Hao He, Xingwei Gao, Alexander Cerjan +1
One of the key features of lasers operating near exceptional points (EPs) is that the gain medium can support an oscillating population inversion above a pump threshold, leading to…
physics.optics2024
Dynamic gain and frequency comb formation in exceptional-point lasers
Xingwei Gao, Hao He, Scott Sobolewski +2
Exceptional points (EPs) -- singularities in the parameter space of non-Hermitian systems where two nearby eigenmodes coalesce -- feature unique properties with applications such a…