Dependence of valence-subband structures on the substrate orientation in ZnSxSe1−x/ZnyMg1−ySzSe1−z quantum wells

Abstract

We present a theoretical investigation of the growth orientation dependence of valence-subband structures in ZnSxSe1−x/ZnyMg1−ySzSe1−z quantum wells grown in the [001], [115], [113], [112], and [111] directions. The results indicate that the in-plane effective mass of the heavy-hole subband in the [111]-oriented structure is substantially smaller than that in the [001] quantum wells. For applications to quantum-well lasers, the lighter effective mass will lead to a smaller threshold current density, and therefore a better laser performance. Our investigations should provide useful guidelines for the design of II-VI quantum-well blue lasers.