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arXiv · 2007.02093

Tensor monopoles and negative magnetoresistance effect in optical lattices

Hai-Tao Ding·Yan-Qing Zhu·Zhi Li·Lubing Shao
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Abstract

We propose that a kind of four-dimensional (4D) Hamiltonians, which host tensor monopoles related to quantum metric tensor in even dimensions, can be simulated by ultracold atoms in the optical lattices. The topological properties and bulk-boundary correspondence of tensor monopoles are investigated in detail. By fixing the momentum along one of the dimensions, it can be reduced to an effective three-dimensional model manifesting with a nontrivial chiral insulator phase. Using the semiclassical Boltzmann equation, we calculate the longitudinal resistance against the magnetic field $B$ and find the negative relative magnetoresistance effect of approximately $ -B^{2} $ dependence when a hyperplane cuts through the tensor monopoles in the parameter space. We also propose an experimental scheme to realize this 4D Hamiltonian by introducing an external cyclical parameter in a 3D optical lattice. Moreover, we show that the quantum metric tensor and Berry curvature can be detected by applying an external drive in the optical lattices.

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Hai-Tao Ding, Yan-Qing Zhu, Zhi Li, Lubing Shao. 2020-07-04. Tensor monopoles and negative magnetoresistance effect in optical lattices. https://doi.org/10.1103/physreva.102.053325

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