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arXiv · 1610.02938

Quantum spin transistor with a Heisenberg spin chain

O. V. Marchukov·A. G. Volosniev·M. Valiente·D. Petrosyan·N. T. Zinner
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Abstract

We propose and analyze a scheme for conditional state transfer in a Heisenberg $XXZ$ spin chain which realizes a quantum spin transistor. In our scheme, the absence or presence of a control spin excitation in the central gate part of the spin chain results in either perfect transfer of an arbitrary state of a target spin between the weakly coupled input and output ports, or its complete blockade at the input port. We also present a possible realization of the corresponding spin chain with a one-dimensional ensemble of cold atoms with strong contact interactions.

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O. V. Marchukov, A. G. Volosniev, M. Valiente, D. Petrosyan, N. T. Zinner. 2016-10-10. Quantum spin transistor with a Heisenberg spin chain. https://doi.org/10.1038/ncomms13070

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