Simulation study of strained layer CdxZn1−xTe–ZnTe quantum well laser structures

The strain introduced at the junction of two mismatched semiconductors reshapes the valence band reducing the density of states. This effect has been successfully exploited to get quantum well (QW) lasers of III–V compounds. In the present study, a ternary system CdxZn1−xTe on ZnTe substrate has been investigated. The effect of x on critical thickness, effective mass, band gap, optical gain and current density has been calculated. This system was chosen as it is useful in blue emission, emission at high temperature, etc. The optical gain increases with x, whereas current density decreases. The laser cavity length and number of QWs have been optimized for different x and temperatures for a given gain.