Efficient amplification of superpositions of coherent states using input states with different parities

TL;DR

This paper presents a practical method for amplifying superpositions of coherent states by mixing differently parited input states at a beam splitter and using homodyne detection for post-selection, achieving high fidelity.

Contribution

It introduces a novel scheme utilizing input states with opposite parities to efficiently amplify superpositions of coherent states with high fidelity.

Findings

Achieves nearly perfect fidelity in amplified superpositions

Uses feasible experimental setup with beam splitter and homodyne detection

Demonstrates effective amplification of superpositions of coherent states

Abstract

We investigate an experimentally feasible scheme for amplification of superpositions of coherent states (SCSs) in light fields. This scheme mixes two input SCSs at a 50:50 beam splitter and performs post-selection by a homodyne detection on one output mode. The key idea is to use two different types of SCSs with opposite parities for input states, which results in an amplified output SCS with a nearly perfect fidelity.