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arXiv · 1901.01887

Non-adiabatic transformation of a spin-chain geometry via local control

P. V. Pyshkin·E. Ya. Sherman·Lian-Ao Wu
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Abstract

We consider transformation from a closed to an open spin chain and vice versa produced by changing single link strength in a pair of neighboring spins. We show that in the non-adiabatic time domain fidelity of such a process can be increased by proper choosing of the control function for spin-spin exchange coupling. We obtain this function for an antiferromagnetic quantum Ising chain and present heuristic reasons restricting possible time-dependences of Hamiltonians applied for a high-fidelity control.

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P. V. Pyshkin, E. Ya. Sherman, Lian-Ao Wu. 2019-01-07. Non-adiabatic transformation of a spin-chain geometry via local control. https://doi.org/10.12693/aphyspola.135.1198

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