# Scheme for coherent-state quantum process tomography via normally-ordered moments

## TL;DR

This paper presents a comprehensive method for characterizing quantum-optical processes using coherent states and normally-ordered moments, enabling efficient identification of multi-mode Gaussian processes and nonclassical features.

## Contribution

It introduces a novel framework for quantum process tomography in optical systems based on normally-ordered moments with scalable probe requirements.

## Key findings

- Superoperator tensors derived for various optical processes
- Method can determine nonclassicality features of quantum states
- Probe number scales linearly with the number of modes

## Abstract

Using coherent states in optical quantum process tomography is a practically-relevant approach. Here, we develop a framework for complete characterization of quantum-optical processes in terms of normally-ordered moments by using coherent states as probes. We derive the associated superoperator tensors for several optical processes. We also show that our technique can be used to determine nonclassicality features of quantum-optical states and processes. Furthermore, we investigate identification of multi-mode Gaussian processes and show that the number of necessary probe coherent states scales linearly with the number of modes.