Quantum controlled-phase-flip gate between a flying optical photon and a Rydberg atomic ensemble

Y M Hao,S Q Gong,X M Lin,G W Lin,Keyu Xia,Y P Niu

doi:10.1038/srep10005

Abstract

Quantum controlled-phase-flip (CPF) gate between a flying photon qubit and a stationary atomic qubit could allow the linking of distant computational nodes in a quantum network. Here we present a scheme to realize quantum CPF gate between a flying optical photon and an atomic ensemble based on cavity input-output process and Rydberg blockade. When a flying single-photon pulse is reflected off the cavity containing a Rydberg atomic ensemble, the dark resonance and Rydberg blockade induce a conditional phase shift for the photon pulse, thus we can achieve the CPF gate between the photon and the atomic ensemble. Assisted by Rydberg blockade interaction, our scheme works in the N-atoms strong-coupling regime and significantly relaxes the requirement of strong coupling of single atom to photon in the optical cavity.

Highlights

With a large number of atoms (N 1), our scheme can work in the single-atom weak-coupling regime, i.e., C 1, which significantly relaxes the requirement of the optical cavity for realization of the quantum CPF gate
They form the standard three-level electromagnetically induced transparency (EIT) configuration21–23, in which the coherent processes are described by interaction
When the single photon is reflected off the cavity containing the atoms in state |0 or |1, the whole state of the system at arbitrary time can be described by Ψ 0(t) or Ψ1(t), with

Summary

Introduction

The frequency of input pulse we can achieve the CPF gate between the photon and the atomic ensemble. The basic building block of our scheme is an ensemble of N Rydberg atoms trapped inside a single-sided optical cavity, which reflects off a flying single-photon pulse. When the single photon is reflected off the cavity containing the atoms in state |0 or |1 , the whole state of the system at arbitrary time can be described by Ψ 0(t) or Ψ1(t) , with

Results

Conclusion