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arXiv · 0809.3555

Electronic interlayer coupling in the LTT phase of La1.79Eu0.2Sr0.01CuO4

M. Huecker
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Abstract

The electronic interlayer transport of the lightly doped antiferromagnet La1.79Eu0.2Sr0.01CuO4 has been studied by means of magneto-resistance measurements. The central problem addressed concerns the differences between the electronic interlayer coupling in the tetragonal low-temperature (LTT) phase and the orthorhombic low-temperature (LTO) phase. The key observation is that the spin-flip induced drop in the c-axis magneto-resistance of the LTO phase, which is characteristic for pure La2-xSrxCuO4, dramatically decreases in the LTT phase. The results show that the transition from orthorhombic to tetragonal symmetry and from collinear to non-collinear antiferromagnetic spin structure eliminates the strain dependent anisotropic interlayer hopping as well as the concomitant spin-valve type transport channel. Implications for the stripe ordered LTT phase of La2-xBaxCuO4 are briefly discussed.

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M. Huecker. 2008-09-21. Electronic interlayer coupling in the LTT phase of La1.79Eu0.2Sr0.01CuO4. https://doi.org/10.1103/physrevb.79.104523

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