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arXiv · 1001.2444

State transfer in static and dynamic spin chains with disorder

David Petrosyan·Georgios M. Nikolopoulos·P. Lambropoulos
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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 inter-spin exchange (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 (XY coupling) disorder, as compared to a much slower but robust adiabatic transfer protocol with time-dependent coupling strengths.

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David Petrosyan, Georgios M. Nikolopoulos, P. Lambropoulos. 2010-01-14. State transfer in static and dynamic spin chains with disorder. https://doi.org/10.1103/physreva.81.042307

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