Hamiltonian tomography in an access-limited setting without state initialization

TL;DR

This paper introduces a method for determining coupling parameters in a spin chain using only measurements on a single particle, without needing state initialization or prior knowledge, effective even with dissipation.

Contribution

The proposed scheme enables Hamiltonian tomography in spin chains with minimal measurement requirements and no state preparation, advancing quantum-dynamics characterization techniques.

Findings

Effective in dissipative and dephasing environments

Requires only time-resolved measurements on one particle

No prior state knowledge or initialization needed

Abstract

We propose a scheme for the determination of the coupling parameters in a chain of interacting spins. This requires only time-resolved measurements over a single particle, simple data post-processing and no state initialization or prior knowledge of the state of the chain. The protocol fits well into the context of quantum-dynamics characterization and is efficient even when the spin-chain is affected by general dissipative and dephasing channels. We illustrate the performance of the scheme by analyzing explicit examples and discuss possible extensions.