Discrete time quantum walk with nitrogen-vacancy centers in diamond coupled to a superconducting flux qubit

TL;DR

This paper presents a scheme for implementing discrete-time quantum walks using nitrogen-vacancy centers in diamond coupled with a superconducting flux qubit, improving previous cavity QED methods by simplifying drive-pulse requirements.

Contribution

The authors propose a novel quantum-electrodynamics scheme that simplifies the implementation of quantum walks with nitrogen-vacancy centers and flux qubits, removing complex pulse-duration variations.

Findings

Scheme can realize quantum walks under realistic conditions

Improves on previous cavity QED proposals by simplifying control requirements

Numerical analysis confirms feasibility of the approach

Abstract

We propose a quantum-electrodynamics scheme for implementing the discrete-time, coined quantum walk with the walker corresponding to the phase degree of freedom for a quasi-magnon field realized in an ensemble of nitrogen-vacancy centres in diamond. The coin is realized as a superconducting flux qubit. Our scheme improves on an existing proposal for implementing quantum walks in cavity quantum electrodynamics by removing the cumbersome requirement of varying drive-pulse durations according to mean quasiparticle number. Our improvement is relevant to all indirect-coin-flip cavity quantum-electrodynamics realizations of quantum walks. Our numerical analysis shows that this scheme can realize a discrete quantum walk under realistic conditions.