Dynamics of Bloch–Zener Oscillations with Tuning Gap

Abstract

In this study, the transient dynamics of Bloch-Zener oscillations (BZOs) in a 1D qubit chain with a controllable band gap are explored. The chain consists of alternating site energies and is subjected to a constant external field. Several tight-binding models were analyzed, including Bloch and Landau-Zener models, to understand the BZOs mechanism. The findings revealed that the band gaps played a crucial role in bridging the intriguing interplay between Bloch oscillations and Landau-Zener transitions. The motion of carriers in real and quasi-momentum spaces is explored and the time evolution of occupancy in mini-bands is calculated. A linearly time-dependent way of tuning the gap is also proposed and non-periodic motion is observed. When the chain is coupled to dispersionless optical phonons, strong coupling leads to large phonon displacements and localizes the carrier wave packets of the qubit states. The findings provide new insights into the behavior of BZOs in complex systems and suggest avenues for future studies.