Polarization bistability in strained 1.3 mu m semiconductor lasers controlled by temperature and external mechanical force

Polarization bistability with hysteresis in 1.3 mu m InGaAsP/lnP ridge waveguide bulk lasers has been achieved at room temperature by a built-in tensile strain with (i) temperature variation and (ii), for the first time, application of an external force. In both cases, four types of emission characteristics are observed: pure TE emission, TE/TM bistability, smooth TE/TM transition and pure TM radiation. It is demonstrated that the hysteresis width can be controlled by both temperature and strain, which opens the possibility to fabricate laser diodes with different switching properties. The physical mechanism responsible for the observed behaviour is discussed.