Introduction

Abstract

Semiconductor quantum structures, such as quantum wires (QWRs) and dots (QDs), are attracting much interest in the field of fundamental physics and novel device application, as described in the previous chapters. The realization of such properties requires extreme control of fabrication tolerance, and nonuniformity in structural dimensions often fatally degrades the advantageous properties. For instance, inhomogeneous broadening of the gain spectrum of QD lasers will result from fabricational variations in the dot size and shape. Quantum dot lasers do not offer significant advantages over conventional bulk lasers unless fabricational tolerances are tightly controlled [1].