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Origin of Magnetoresistance Anomalies in Antiferromagnetic YBa_{2}Cu_{3}O_{6+x}

A. S. Moskvin·Yu. D. Panov
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Abstract

Specific d-wave angular dependence of the in-plane magnetoresistence in antiferromagnetic tetragonal YBa_{2}Cu_{3}O_{6+x} (x~0.3) on orientation of the external magnetic field in (a,b) plane is assigned to the effective hole transport through low lying excited purely oxygen doublet O2pe_u state, not the ground b_{1g}(d_{x^2-y^2}) state. External magnetic field determines the orientation of the strong exchange field for the spin-triplet b_{1g}e_u:{}^{3}E_u state of the hole CuO_4 center and due to the spin-orbital coupling results in either orbital polarization of the E_u doublet giving rise to the spatial anisotropy of the hole transport. Experimental data allow to estimate parameter of the effective spin Hamiltonian.

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A. S. Moskvin, Yu. D. Panov. 2002-07-08. Origin of Magnetoresistance Anomalies in Antiferromagnetic YBa_{2}Cu_{3}O_{6+x}. https://doi.org/10.1016/s0038-1098(02)00127-8

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