A Symmetric Parity–Time Coupled Optoelectronic Oscillator Using a Polarization–Dependent Spatial Structure
- Resource Type
- article
- Authors
- Fengling Zhang; Xiaodong Lin; Zhengmao Wu; Guangqiong Xia
- Source
- Photonics, Vol 10, Iss 11, p 1236 (2023)
- Subject
- parity–time symmetry
coupled optoelectronic oscillator
gain coefficient
coupling coefficient
orthogonal polarization
phase noise
Applied optics. Photonics
TA1501-1820
- Language
- English
- ISSN
- 2304-6732
We propose and experimentally investigate a symmetric parity-time (PT) coupled optoelectronic oscillator (COEO) based on a polarization-dependent spatial structure. In such a COEO system, the gain/loss and coupling coefficients of two orthogonal polarization optical waves can be controlled by adjusting the polarization controller (PC) and the bias voltage of a Mach-Zehnder modulator (MZM). The single-mode selection of a microwave signal can be implemented by the PT symmetry breaking of a special mode. The performance of the proposed COEO is experimentally examined, and a 10.0 GHz microwave signal with a phase noise of −109.1 dBc/Hz @ 10 kHz and a side mode suppression ratio of 51.4 dB is generated. Moreover, an optical frequency comb with a comb tooth spacing of 10.0 GHz and a bandwidth of 100 GHz within a 10 dB amplitude variation can be simultaneously generated.