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arXiv · 1811.02950

Quantum network transfer and storage with compact localized states induced by local symmetries

M. Röntgen·C. V. Morfonios·I. Brouzos·F. K. Diakonos·P. Schmelcher
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Abstract

We propose modulation protocols designed to generate, store and transfer compact localized states in a quantum network. Induced by parameter tuning or local reflection symmetries, such states vanish outside selected domains of the complete system and are therefore ideal for information storage. Their creation and transfer is here achieved either via amplitude phase flips or via optimal temporal control of inter-site couplings. We apply the concept to a decorated, locally symmetric Lieb lattice where one sublattice is dimerized, and also demonstrate it for more complex setups. The approach allows for a flexible storage and transfer of states along independent paths in lattices supporting flat energetic bands. The generic network and protocols proposed can be utilized in various physical setups such as atomic or molecular spin lattices, photonic waveguide arrays, and acoustic setups.

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M. Röntgen, C. V. Morfonios, I. Brouzos, F. K. Diakonos, P. Schmelcher. 2018-11-07. Quantum network transfer and storage with compact localized states induced by local symmetries. https://doi.org/10.1103/physrevlett.123.080504

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