Direct Estimation of Single- and Two-Qubit Hamiltonians and Relaxation Rates

TL;DR

This paper introduces a new method for directly estimating single- and two-qubit Hamiltonian parameters and relaxation rates using only a single measurement device, leveraging quantum correlations for efficient quantum system characterization.

Contribution

It presents a novel approach that enables direct Hamiltonian and relaxation rate estimation with a single Bell-state analyzer, improving partial characterization capabilities.

Findings

Effective estimation of Hamiltonian parameters demonstrated

Method utilizes quantum correlations for measurement efficiency

Suitable for partial system characterization

Abstract

We provide a novel approach for characterization of quantum Hamiltonian systems via utilizing a single measurement device. Specifically, we demonstrate how external quantum correlations can be used for Hamiltonian identification tasks. We explicitly introduce experimental procedures for direct estimation of single- and two-qubit Hamiltonian parameters, and also for simultaneous estimation of transverse and longitudinal relaxation rates, using a single Bell-state analyzer. An advantage of our method over the earlier approaches is that it has a built-in feature which makes it suitable for partial characterization of Hamiltonian parameters.