On Quantum Channel Estimation with Minimal Resources

TL;DR

This paper identifies the minimal experimental resources needed for unique quantum channel estimation, develops a globally converging algorithm, and demonstrates through simulations that minimal settings suffice for accurate estimates.

Contribution

It introduces a minimal resource framework for quantum channel estimation and a Newton-type algorithm ensuring physically valid solutions.

Findings

Minimal resources guarantee unique solutions in quantum channel estimation.

The proposed algorithm converges globally to physically admissible solutions.

Simulations show minimal settings are sufficient for accurate estimation.

Abstract

We determine the minimal experimental resources that ensure a unique solution in the estimation of trace-preserving quantum channels with both direct and convex optimization methods. A convenient parametrization of the constrained set is used to develop a globally converging Newton-type algorithm that ensures a physically admissible solution to the problem. Numerical simulations are provided to support the results, and indicate that the minimal experimental setting is sufficient to guarantee good estimates.