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arXiv · 2306.02818

Lattice source for charge and spin inhomogeneity in 2D perovskite cuprates

Vladimir A. Gavrichkov·Semyon I. Polukeev
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Abstract

In the work we highlight the structural features of 2D perovskite cuprates (tilted CuO$_6$ octahedra with different orientation with respect to spacer rocksalt layers), where sources of charge and spin inhomogeneity can be hidden. We used the impurity Anderson model with the Jahn-Teller(JT) local cells to show the charge inhomogeneity arises at any low doping concentration $x$, but disappears when the doping level exceeds threshold concentration $x_c$, and the lower the magnitudes $x_c$, the more JT region square. It is expected that spontaneous chiral symmetry breaking in the dynamic JT state of the stripe CuO$_2$ layer as a whole can lead to the appearance of the goldstone phonon mode. As consequence, the giant thermal Hall effect could be observed in the 2D perovskite cuprates with CuO$_6$ octahedra, rather than with CuO$_4$ squares, e.g. in Tl-based $n$ layer cuprates or cuprates based on the infinite-layer CaCuO$_2$ structure.

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Vladimir A. Gavrichkov, Semyon I. Polukeev. 2023-06-05. Lattice source for charge and spin inhomogeneity in 2D perovskite cuprates. https://arxiv.org/abs/2306.02818

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