Random matrix models for decoherence and fidelity decay in quantum information systems

TL;DR

This paper introduces random matrix models to analyze decoherence and fidelity decay in quantum information systems, emphasizing their disordered environment characteristics and analytical tractability, with validation against experimental data.

Contribution

It presents a powerful random matrix approach for modeling decoherence and fidelity decay, highlighting its analytical advantages and experimental validation in quantum information contexts.

Findings

Random matrix models accurately predict fidelity decay.

Analytic solutions are feasible due to model integrability.

Experimental results align well with theoretical predictions.

Abstract

This course aims to introduce the student to random matrix models for decoherence and fidelity decay. They present a very powerful alternate approach, that emphasizes the disordered character of many environments and uncontrollable perturbations/couplings. The inherent integrability of such models makes analytic studies possible. We limit our considerations to linear response treatment, as high fidelity and small decoherence are the backbone of quantum information processes. For fidelity decay, where experimental results are available, a comparison with experiments shows excellent agreement with random matrix theory predictions.