Magnetoresistance calculations for a two-dimensional electron gas with unilateral short-period strong modulation

The linear response theory is used to describe magnetoresistance oscillations of short-period unilateral superlattices with strong modulation (or alternatively arrays of coupled quantum wires). The semiclassical description of this system fails for strong magnetic fields (magnetic breakdown) and we employ a simple fully quantum-mechanical tight-binding model (owing to the fact that coupling between two neighboring wires is much smaller than the height of barrier between them) in conjunction with Kubo’s formula instead. The resulting magnetoresistance data nicely compare to the experiments while the model opens good intuitive insight into the effects taking place in the system.