The effect of external stress on the properties of AlGaAs/GaAs single quantum well laser diodes

The change of spectrum of the AlGaAs/GaAs single quantum well laser diode is measured under the application of uniform uniaxial in-plane tensile and compressive stress. In the range of the tensile stress we apply (up to 597 MPa), the wavelength increases linearly at a rate of 5.3 nm GPa−1. The energy band gap decreases with the tensile stress with the slope of −10 meV GPa−1, which is close to the theoretical change of the heavy hole band edge with respect to the conduction band edge. There is a shorter wavelength peak existing on the spectrum as the tensile stress increases, suggesting a transition from the conduction band to a higher energy valence band. For the compressive stress (up to −516 MPa), the wavelength decreases with the stress, but it shows an abrupt reduction from −162 to −200 MPa. The threshold current also varies as a result of the change of the energy band structure.