Edge-locking and quantum control in highly polarized spin chains

Masudul Haque

doi:10.1103/physreva.82.012108

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arXiv · 0906.0996

Edge-locking and quantum control in highly polarized spin chains

Masudul Haque

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Abstract

For an open-boundary spin chain with anisotropic Heisenberg (XXZ) interactions, we present states in which a connected block near the edge is polarized oppositely to the rest of the chain. We show that such blocks can be `locked' to the edge of the spin chain, and that there is a hierarchy of edge-locking effects at various orders of the anisotropy. The phenomenon enables dramatic control of quantum state transmission: the locked block can be freed by flipping a single spin or a few spins.

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Masudul Haque. 2009-06-05. Edge-locking and quantum control in highly polarized spin chains. https://doi.org/10.1103/physreva.82.012108

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