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arXiv · 1507.05919

Quantum spin chains with fractional revival

Vincent X. Genest·Luc Vinet·Alexei Zhedanov
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Abstract

A systematic study of fractional revival at two sites in $XX$ quantum spin chains is presented and analytic models with this phenomenon are exhibited. The generic models have two essential parameters and a revival time that does not depend on the length of the chain. They are obtained by combining two basic ways of realizing fractional revival in a spin chain each bringing one parameter. The first proceeds through isospectral deformations of spin chains with perfect state transfer. The second arises from the recurrence coefficients of the para-Krawtchouk polynomials with a bi-lattice orthogonality grid. It corresponds to an analytic model previously identified that can possess perfect state transfer in addition to fractional revival.

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Vincent X. Genest, Luc Vinet, Alexei Zhedanov. 2015-07-21. Quantum spin chains with fractional revival. https://doi.org/10.1016/j.aop.2016.05.009

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