Polarization Switching in a 1.5 um Wavelength Single-Mode Vertical Cavity Surface Emitting Laser under Modulated Optical Beam Injection Control

We report an experimental demonstration of potentially high-speed polarization switching in a 1.5 mum wavelength single-mode vertical cavity surface emitting laser (VCSEL) under modulated injection laser beam control. The polarization switching up to 200 MHz between the two inherent linear polarization modes of the single-mode VCSEL was demonstrated when a modulated optical beam from an external VCSEL whose polarization was orthogonal to the free-running polarization state of the VCSEL was injected. The dynamical bistability of the VCSEL´s two polarization states was well observed at a driving current above the threshold (I = 2.14I _th). An optical injection power of -23.24 dBm was used for the polarization switching operation.