  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.
