# CNOT gate on reverse photon modes in ring cavity

## TL;DR

This paper proposes a method to implement a CNOT quantum gate using reverse photon modes in a ring cavity coupled with a single atom, providing analytical solutions and experimental considerations for optical quantum computing.

## Contribution

It introduces a novel approach to realize a CNOT gate via reverse photon modes in a ring cavity, with an analytical framework and practical implementation insights.

## Key findings

- Analytical solution for photon mode evolution
- Condition for CNOT gate implementation derived
- Discussion on on-chip experimental feasibility

## Abstract

Photon modes of reverse rotation in ring QED-cavity coupled with single atom are considered. By applying Schrieffer-Wolf transformation for the off-resonant light-atom interaction, an effective Hamiltonian of the evolution of the photon modes is obtained. Heisenberg equations for the input-output photon mode operators are written and the expression for the system wave function is found. The obtained analytical solution shows the condition of the control NOT quantum gate implementation. Possible on a chip experimental implementation and recommendations for the construction of optical quantum computer using this gate are considered.