On Rabi oscillations between Bloch bands

TL;DR

This paper investigates Rabi oscillations between Bloch bands in biased superlattices, deriving approximate solutions and identifying regimes of coupling strength, supported by numerical comparisons.

Contribution

It introduces a reduction of the problem to a Whittaker--Hill type equation and explores approximations for different coupling regimes.

Findings

Weak and strong coupling regimes identified

Approximate analytical solutions proposed

Numerical results validate the approximations

Abstract

We study Rabi oscillations between the bands of an arbitrary biased superlattice in a tight-binding model. We reduce the problem to an equation of Whittaker--Hill type and, in absence of any known solutions in closed form, discuss different approximations to describe the oscillations between the Bloch bands. We identify regimes of weak and strong inter-band coupling and compare predictions for these Rabi oscillations to numerical results.