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arXiv · 0710.5325

Anisotropies in insulating La$_{2-x}$Sr$_x$CuO$_4$: angular resolved photoemission and optical absorption

O. P. Sushkov·Wenhui Xie·O. Jepsen·O. K. Andersen·G. A. Sawatzky
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Abstract

Due to the orthorhombic distortion of the lattice, the electronic hopping integrals along the $a$ and $b$ diagonals, the orthorhombic directions, are slightly different. We calculate their difference in the LDA and find $t_{a}^{\prime}-t_{b}^{\prime}\approx 8 $meV. We argue that electron correlations in the insulating phase of La$_{2-x}$Sr$_{x}$CuO$_{4}$, i. e. at doping $x\leq 0.055,$ dramatically enhance the $(t_{a}^{\prime}-t_{b}^{\prime}) $-splitting between the $a$- and $b$-hole valleys. In particular, we predict that the intensity of both angle-resolved photoemission and of optical absorption is very different for the $a$ and $b$ nodal points.

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O. P. Sushkov, Wenhui Xie, O. Jepsen, O. K. Andersen, G. A. Sawatzky. 2007-10-29. Anisotropies in insulating La$_{2-x}$Sr$_x$CuO$_4$: angular resolved photoemission and optical absorption. https://doi.org/10.1103/physrevb.77.035124

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