Decoherence of Rabi oscillations of electronic spin states in a double quantum dot

TL;DR

This paper investigates how charge fluctuations cause decoherence in Rabi oscillations of two-electron spin states in a double quantum dot, highlighting temperature-dependent effects on quantum coherence.

Contribution

It provides a detailed analysis of charge fluctuation effects on spin decoherence, considering both classical and quantum regimes, and identifies dominant decoherence mechanisms at different temperatures.

Findings

Charge fluctuations significantly impact Rabi oscillation coherence.

High temperature decoherence is dominated by state fluctuations.

Low temperature decoherence mainly due to low frequency energy fluctuations.

Abstract

We study the role of charge fluctuations in the decoherence of Rabi oscillations between spin states |$\uparrow \downarrow$>, |$\downarrow \uparrow$> of two electrons in a double dot structure. We consider the effects of fluctuations in energy and in the quantum state of the system, both in the classical and quantum limit. The role of state fluctuations is shown to be of leading order at sufficiently high temperature, applicable to actual experiments. At low temperature the low frequency energy fluctuations are the only dominant contribution.