Generalized Cluster Correlation Expansion theory for STIRAP processes in the presence of a spin bath

TL;DR

This paper extends the Cluster Correlation Expansion theory to analyze STIRAP processes in systems coupled to interacting spin baths, demonstrating robustness of the protocol in silicon vacancy systems with nuclear spin environments.

Contribution

It introduces a generalized CCE approach for STIRAP in spin bath systems and applies it to silicon vacancy centers in SiC, showing protocol robustness.

Findings

Small/medium spin baths do not affect STIRAP efficiency.

Identified parameter regimes for successful population transfer.

Validated the generalized CCE method for complex spin environments.

Abstract

The Stimulated Raman Adiabatic Passage (STIRAP) is applied to a system coupled to a bath made of fully-interacting two-level systems, whose dynamics is studied exploiting the generalized Cluster Correlation Expansion (gCCE) theory. We specialize our analysis to a negatively charged silicon vacancy (SiV-1) in non-purified 4H-SiC to assess the possibility of transferring population between two states of the ground manifold, also taking into account the interaction with a spherical nuclear spin bath formed by nuclei of 29Si and 13C. For this system, it is demonstrated that the presence of a small/medium sized bath has no effect on the protocol, finding in particular a set of parameter values for an efficient STIRAP process.