Abstract

We report a new kind of optical bistability, polarization bistability,¹ in semiconductor lasers. The phenomenon is observed in some InGaAsP/lnP lasers operating near the polarization transition temperature, which is characteristic of each individual laser. In this temperature regime, the lasers operate in a pure TM₀₀ mode at low injection currents and switch operation to a pure TE₀₀ mode at high injection currents. Large hysteresis loops with high contrast ratios are observed in the polarization-resolved power vs current characteristics, while the total power exhibits only slight changes in the hysteresis. The switching behavior of the TE mode is, therefore, complementary to that of the TM mode. Switching between the two stable polarization states by injection of short current pulses is also demonstrated.

© 1985 Optical Society of America