Modelling of quantum information processing with Ehrenfest guided tra jectories: a case study

TL;DR

This paper introduces a numerical method using Ehrenfest guided trajectories to accurately model quantum information processing, specifically entangling gates, in complex spin-boson systems at various temperatures.

Contribution

The study demonstrates the effectiveness of multi-configurational Ehrenfest trajectories for simulating quantum gates in spin-boson models, including finite temperature effects and a wide range of mediating modes.

Findings

Converged results for Choi fidelity of quantum gates.

Effective modeling of spin-boson interactions at finite temperatures.

Applicability to photonic crystals and ion trap systems.

Abstract

We apply a numerical method based on multi-configurational Ehrenfest tra jectories, and demonstrate converged results for the Choi fidelity of an entangling quantum gate between two two-level systems interacting through a set of bosonic modes. We consider both spin-boson and rotating wave Hamiltonians, for various numbers of mediating modes (from 1 to 100), and extend our treatment to include finite temperatures. Our results apply to two-level impurities interacting with the same band of a photonic crystal, or to two distant ions interacting with the same set of motional degrees of freedom.