dc-switchable and single-nanocrystal-addressable coherent population transfer

TL;DR

This paper demonstrates a method for coherent population transfer in silicon and germanium nanocrystals, using stimulated Raman adiabatic passage, which can be switched off with a dc voltage and used for individual nanocrystal addressing.

Contribution

It provides a theoretical framework for efficient, switchable population transfer in solid-state nanocrystals, advancing quantum control techniques.

Findings

Transfer efficiency spectra show Fano resonances.

Transfer can be switched off with a dc voltage via the Stark effect.

Potential for addressing individual nanocrystals within an ensemble.

Abstract

Achieving coherent population transfer in the solid-state is challenging compared to atomic systems due to closely spaced electronic states and fast decoherence. Here, within an atomistic pseudopotential theory, we offer recipes for the stimulated Raman adiabatic passage in embedded silicon and germanium nanocrystals. The transfer efficiency spectra displays characteristic Fano resonances. By exploiting the Stark effect, we predict that transfer can be switched off with a dc voltage. As the population transfer is highly sensitive to structural variations, with a choice of a sufficiently small two-photon detuning bandwidth, it can be harnessed for addressing individual nanocrystals within an ensemble.