Preparation of Pure Gaussian States via Cascaded Quantum Systems

TL;DR

This paper introduces a method to generate pure Gaussian states using cascaded quantum harmonic oscillators, avoiding direct interactions, which simplifies experimental implementation.

Contribution

It demonstrates that any pure Gaussian state can be produced by cascading one-dimensional open quantum harmonic oscillators without direct Hamiltonian interactions.

Findings

Any pure Gaussian state can be generated via cascaded oscillators

The method avoids direct interaction Hamiltonians

Example provided for two-mode squeezed states

Abstract

This paper provides an alternative approach to the problem of preparing pure Gaussian states in a linear quantum system. It is shown that any pure Gaussian state can be generated by a cascade of one-dimensional open quantum harmonic oscillators, without any direct interaction Hamiltonians between these oscillators. This is physically advantageous from an experimental point of view. An example on the preparation of two-mode squeezed states is given to illustrate the theory.