Symmetry breaking in pseudomorphic V-groove quantum wires

Pseudomorphic crescent-shaped quantum wires are shown to exhibit size-dependent symmetry breaking due to an anisotropic strain distribution. We predict level degeneracies and an increased carrier lifetime. As a model system ${\mathrm{In}}_{0.2}$ ${\mathrm{Ga}}_{0.8}$As/${\mathrm{Al}}_{0.2}$ ${\mathrm{Ga}}_{0.8}$As quantum wires are simulated with finite-element analysis to obtain the strain tensor. Within the confinement potentials, which are strongly modified by the strain-induced potentials and the piezoelectric field, the single-particle Schrödinger equation is solved for electrons and holes.