Control of Polarization Phase Offset in Low Threshold Polarization Switching VCSELs

Both polarization switching and control over the angle between polarization states is demonstrated. A novel dual intracavity contacted vertical-cavity surface-emitting laser utilizing asymmetric current injection is tested. Large extinction ratios 21 dB and a record-low threshold current of 0.19 mA is achieved for such devices. Control over the phase offset between two polarization states is accomplished by rotating current injection direction relative to the axis. The phase offset between two polarization states is shown to follow a trigonometric function with maximum offsets along the and directions and minimum offsets along the and directions.