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

TL;DR

This study investigates how the transition from orthorhombic to tetragonal symmetry in La1.79Eu0.2Sr0.01CuO4 affects electronic interlayer coupling, revealing a significant reduction in spin-flip related magneto-resistance effects.

Contribution

It provides new insights into the impact of structural phase transition on interlayer electronic transport in lightly doped cuprates.

Findings

Spin-flip induced magneto-resistance drop decreases in LTT phase

Transition from orthorhombic to tetragonal eliminates anisotropic interlayer hopping

Implications for stripe-ordered phases in related cuprates

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.