State transfer in static and dynamic spin chains with disorder

Abstract

We examine the speed and fidelity of several protocols for state or single excitation transfer in finite spin chains subject to diagonal and off-diagonal disorder. We find that, for a given chain length and maximal achievable interspin exchange ($\mathit{XY}$) coupling strength, the optimal static spin-coupling protocol, implementing the fastest state transfer between the two ends of the chain, is more susceptible to off-diagonal ($\mathit{XY}$ coupling) disorder, as compared to a much slower but robust adiabatic transfer protocol with time-dependent coupling strengths.