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arXiv · 1706.04974

Squeezed Dirac and Topological Magnons in a Bosonic Honeycomb Optical Lattice

S. A. Owerre·J. Nsofini
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Abstract

Quantum information storage using charge-neutral quasiparticles are expected to play a crucial role in the future of quantum computers. In this regard, magnons or collective spin-wave excitations in solid-state materials are promising candidates in the future of quantum computing. Here, we study the quantum squeezing of Dirac and topological magnons in a bosonic honeycomb optical lattice with spin-orbit interaction by utilizing the mapping to quantum spin-$1/2$ XYZ Heisenberg model on the honeycomb lattice with discrete Z$_2$ symmetry and a Dzyaloshinskii-Moriya interaction. We show that the squeezed magnons can be controlled by the Z$_2$ anisotropy and demonstrate how the noise in the system is periodically modified in the ferromagnetic and antiferromagnetic phases of the model. Our results also apply to solid-state honeycomb (anti)ferromagnetic insulators.

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S. A. Owerre, J. Nsofini. 2017-06-15. Squeezed Dirac and Topological Magnons in a Bosonic Honeycomb Optical Lattice. https://doi.org/10.1088/1361-648x%2Faa8dcb

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