The existence of perfect state transfer in quantum spin networks based on integral circulant graphs has been considered recently by Saxena, Severini and Shparlinski. We give the simple condition for characterizing integral circulant graphs allowing the perfect state transfer in terms of its eigenvalues. Using that we complete the proof of results stated by Saxena, Severini and Shparlinski. More...

Near-future realisations of quantum technologies, from simple state-generation tasks [1–3] to analogue quantum simulation [4], will be small scale and will rely on intrinsic properties of the system to facilitate as much of their functionality as possible, rather than trying to impose error-prone operations to strong-arm the system into performing tasks. For example, existing quantum simulators...