Deterministic Single-Photon Adder and Subtractor

TL;DR

This paper introduces a new theoretical framework for single-photon addition and subtraction operations in quantum information, addressing flaws in previous models and proposing deterministic implementations with coherence preservation.

Contribution

It develops a Kraus operator-based theory for SPAs and SPSs and proposes a method for their deterministic realization using three-level atoms.

Findings

Kraus operator framework overcomes flaws in ladder-operator models

Deterministic SPAs and SPSs can be realized with three-level atoms

Control pulses improve operation performance and coherence preservation

Abstract

Single-photon addition and subtraction are fundamental operations in quantum information processing. Traditionally, the behavior of a single-photon adder (SPA) and single-photon subtractor (SPS) has been theoretically described using creation and annihilation operators, respectively. However, we demonstrate that this ladder-operator-based description contains significant theoretical flaws. To address these issues, we develop a theoretical framework based on Kraus operators, applicable to both coherent and incoherent SPAs and SPSs. Furthermore, we propose a method for realizing deterministic SPAs and SPSs of a cavity mode using three-level atoms. We analyze the effects of these operations on various quantum states. Additionally, we demonstrate that the use of a control pulse could enhance the performance of SPAs and SPSs, effectively preserving the quantum coherence of the resulting photon state.