[9a-Z23-1~6] 4.2 Photonics Devices, Photonic Integrated Circuit and Silicon Photonics

▲ [9a-Z23-5] State-switching around a Fourth-order Exceptional Point in an Optical Microcavity

〇(D)Arnab Laha¹, Dinesh Beniwal², Somnath Ghosh¹ (1.IIT Jodhpur, 2.NISER Bhubaneswar)

Keywords:Open system, Optical microcavity, Exceptional Points

Exceptional points (EPs) are the topological branch-point singularities in open (non-Hermitian) systems, where coupled eigenvalues and the corresponding eigenstates coalesce. Here, we report a gain-loss assisted tri-layer Fabry-Pérot type optical microcavity to host a fourth-order EP with a simultaneous presence of three connecting second-order EPs, where successive state conversion among four coupled states around the embedded fourth-order EP has been explored for the first time.