Magneto-optical studies of the energy spectrum of confined electrons in isolated one-dimensional channels

Abstract

The energy spectra of isolated one-dimensional (1D) electron channels have been studied by photoluminescence in zero and finite magnetic fields. Starting from a modulation-doped GaAsAlGaAs heterojunction, with special low concentration Be δ-doping in the buffer layer, arrays of periodic quantum wires (period = 290nm, width = 160nm–170nm) were prepared from holographically defined masks and reactive ion etching. Strong PL was observed even though the trenches between the wires were deeper than the active layers thereby ensuring that the 1D channels were electronically totally decoupled. We report the first direct observation of 1D subbands at zero magnetic field (B) and, at small B, a quadratic dispersion of the 1D subband edge.