Bloch-like oscillations in a one-dimensional lattice with long-range correlated disorder

TL;DR

This paper investigates electron dynamics in a one-dimensional lattice with long-range correlated disorder, revealing Bloch-like oscillations and identifying the bandwidth of extended states consistent with theoretical predictions.

Contribution

It demonstrates Bloch-like oscillations in a disordered lattice with power-law correlations, confirming the existence and bandwidth of delocalized states predicted by theory.

Findings

Bloch-like oscillations observed between mobility edges

Bandwidth of extended states matches theoretical predictions

Supports phase of delocalized states at the band center

Abstract

We study the dynamics of an electron subjected to a uniform electric field within a tight-binding model with long-range-correlated diagonal disorder. The random distribution of site energies is assumed to have a power spectrum $S(k) \sim 1/k^{\alpha}$ with $\alpha > 0$. Moura and Lyra [Phys. Rev. Lett. {\bf 81}, 3735 (1998)] predicted that this model supports a phase of delocalized states at the band center, separated from localized states by two mobility edges, provided $\alpha > 2$. We find clear signatures of Bloch-like oscillations of an initial Gaussian wave packet between the two mobility edges and determine the bandwidth of extended states, in perfect agreement with the zero-field prediction.