Near-threshold high spin amplification in a 1300 nm GaInNAs spin laser

Using continuous-wave optical pumping of a spin-VCSEL at room temperature, we find high spin amplification of the pump close to threshold within the communications wavelength window, here at 1300 nm. This facilitates a strong switch from left to right circularly polarised light emission, which has potential applications in polarisation encoding for data communications. We use a simple spin flip model to fit the experimental results and discuss the VCSEL parameters that affect this amplification

Experimental demonstration of all-optical PolMux RoF system with multiservice transmission

In this paper, a Radio-over-Fiber (RoF) system is proposed by combining optical carrier suppression (OCS) and polarization multiplexing (PolMux) techniques in all-optical mode to enable multi-service transmission. Previous studies on RoF system only exploited multi-service transmission over low radio frequency (RF) oscillator-based PolMux, subcarrier multiplexing (SCM) and wavelength division multiplexing (WDM) techniques. Hence, herein, PolMux jointly with OCS techniques are exploited as a new medium of multiplexing in RoF system. Essentially, two contributions are unveiled, firstly the combination of all optical OCS and PolMux for RoF technology to enable multi-service transmission, and secondly an end-to-end all-optical transmission with the inclusion of wireless medium at millimeter wave (mmWave) frequency. The results indicate a highly reliable OCS-PolMux topology, where the EVM deterioration due to polarization leakage factor was only 1% to 2% for both services transmitted at the same frequency. Most importantly, the proposed system demonstrated an end-to-end system transmission with optical receiver power budget of up to 6 dB