Experimental analysis of temperature dependence of oscillation wavelength in quantum-well FP semiconductor lasers

We experimentally evaluated the temperature dependence of the oscillation wavelength in 1.3-μm GaInAsP-InP strained multiple-quantum-well (MQW) semiconductor lasers compared to bulk lasers. The temperature dependence of the oscillation wavelength can be characterized by two newly introduced coefficients α₁ and α₂ which are the gain peak wavelength shift coefficients under the constant current condition and under the constant temperature condition, respectively. These two coefficients of various MQW structure lasers are the same as those of bulk lasers. This result means that the oscillation wavelength shift coefficient dλ/dT is only a function of the characteristic temperature T₀. The higher T₀ induces the large temperature dependence of the oscillation wavelength, When the characteristic temperature T₀ is equal to the characteristic temperature T_ltr of the transparency current I_tr, the oscillation wavelength shift coefficient dλ/dT takes the maximum value which is determined by the thermally induced bandgap narrowing effect dλ _g/dT. One possibility to solve the paradox between a high characteristic temperature T₀ and the small temperature dependence of the oscillation wavelength is the introduction of the temperature-independent leakage current