English

Power Spectrum Identification for Quantum Linear Systems

Quantum Physics 2019-01-04 v2

Abstract

In this paper we investigate system identification for general quantum linear systems. We consider the situation where the input field is prepared as stationary (squeezed) quantum noise. In this regime the output field is characterised by the power spectrum, which encodes covariance of the output state. We address the following two questions: (1) Which parameters can be identified from the power spectrum? (2) How to construct a system realisation from the power spectrum? The power spectrum depends on the system parameters via the transfer function. We show that the transfer function can be uniquely recovered from the power spectrum, so that equivalent systems are related by a symplectic transformation.

Keywords

Cite

@article{arxiv.1612.02681,
  title  = {Power Spectrum Identification for Quantum Linear Systems},
  author = {Matthew Levitt and Madalin Guta and Hendra I. Nurdin},
  journal= {arXiv preprint arXiv:1612.02681},
  year   = {2019}
}

Comments

10 pages, 2 figures, submitted to Automatica. arXiv admin note: text overlap with arXiv:1608.01227

R2 v1 2026-06-22T17:17:33.847Z