Localization in semiconductor quantum-wire nanostructures

Localization properties of quasi-one-dimensional quantum-wire nanostructures are investigated using the transfer-matrix Lyapunov-exponent technique. We calculate the localization length as a function of the effective mean-field mobility assuming the random disorder potential to arise from dopant-induced short-range δ-function or finite-range Gaussian impurity scattering. The localization length increases approximately linearly with the effective mobility, and is also enhanced by finite-range disorder. There is a sharp reduction in the localization length when the chemical potential crosses into the second subband.