Efficient population transfer in a quantum dot exciton under phonon-induced decoherence via shortcuts to adiabaticity

TL;DR

This paper demonstrates efficient quantum state transfer in a quantum dot using shortcuts to adiabaticity, effectively mitigating phonon-induced decoherence at low temperatures, with potential applications in quantum photonics.

Contribution

It introduces a method employing shortcut to adiabaticity pulses for population transfer in quantum dots, accounting for phonon effects and optimizing transfer efficiency.

Findings

High transfer efficiency below 20 K with pulse durations up to 10 ps.

Efficiency drops at higher temperatures except with subpicosecond pulses.

Delta pulse approach achieves fast population inversion at elevated temperatures.

Abstract

In the present study, we apply shortcut to adiabaticity pulses (time-dependent Rabi frequency and detuning) for the efficient population transfer from the ground to the exciton state in a GaAs/InGaAs quantum dot with phonon-induced dephasing. We use the time-evolving matrix product operator (TEMPO) method to propagate system in time and find that, for temperatures below $ 20 \ \text{K} $ and pulse duration up to $ 10 \ \text{ps} $, a very good transfer efficiency is obtained in general. We explain these results using a Bloch-like equation derived from a generalized Lindblad equation, which adequately describes system dynamics at lower temperatures. For higher temperatures, the transfer efficiency is significantly reduced except for subpicosecond pulses, where the shortcut Rabi frequency reduces to a delta pulse attaining a fast population inversion. The present work is expected to find application in quantum technologies which exploit quantum dots for single-photon generation on demand.