An 850-nm InAlGaAs strained quantum-well vertical-cavity surface-emitting laser grown on GaAs (311)B substrate with high-polarization stability

The polarization stability of 850-nm InAlGaAs strained quantum-well (QW) vertical-cavity surface-emitting laser (VCSEL) grown on GaAs (311)B substrate was investigated by comparing it with that of GaAs unstrained QW VCSEL grown on GaAs (311)B substrate. Photoluminescence measurement showed that strained QWs grown on GaAs (311)B substrate had larger anisotropy in optical gain than unstrained QWs. The VCSEL with strained QWs showed an orthogonal polarization suppression ratio (OPSR) as high as 21 dB under CW operation. Time-dependent OPSR measurement indicated that the strained QW VCSEL had higher polarization stability than the unstrained QW VCSEL under zero-bias modulation.