Dressed-state scheme for a fast CNOT gate

TL;DR

This paper presents a rapid, feasible dressed-state scheme for implementing a high-fidelity CNOT gate in cavity QED systems, avoiding adiabatic constraints and demonstrating robustness against decoherence through numerical simulations.

Contribution

The paper introduces a novel dressed-state approach for fast CNOT gate implementation in cavity QED, eliminating the need for adiabatic conditions and enhancing experimental feasibility.

Findings

High average fidelity achieved in simulations

Short gate operation time demonstrated

Robustness against atomic spontaneous emission and photon leakage

Abstract

A highly feasible dressed-state scheme, which greatly speeds up the adiabatic population transfer of a quantum system, is applied for implementing a fast CNOT gate in a cavity QED system. The cavity QED system consists of two identical five-level atoms which are respectively trapped in two optical cavities connected by a fiber. With the help of quantum Zeno dynamics, the CNOT gate is constructed by three steps with six pulses. Because the adiabatic condition is not necessary to be considered and all of the pulses are smoothly turned on and off, the scheme is fast and feasible in experiment. Numerical simulations indicate that the average fidelity for constructing the CNOT gate is quite high and the gate operation time is relatively short. Moreover, the effects on the fidelity of the atomic spontaneous emission and the photon leakages from the cavities are discussed by the master equation and the result shows the scheme is robust against the decoherence.