Polarization RIN of VCSEL subject to modulation signal with variable polarization angle of optical feedback

Vertical-cavity surface-emitting laser (VCSEL) devices are being used in both optical fibre and optical wireless communications. In this paper, the influence of variable polarization angle θp of optical feedback (OF) with the modulation signal on the relative intensity noise (RIN) of VCSEL is experimentally investigated. The RIN characteristic is presented with and without the modulation signal under rotated θp of the OF. A minimum RIN of −156 dB/Hz with OF at dominant mode is achieved over the entirely range of θp. However, the RIN level is degraded to −139 dB/Hz under modulation signal in presence of OF.