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arXiv · 2203.00558

Evolution of magnetic stripes under uniaxial stress in La$_{1.885}$Ba$_{0.115}$CuO$_4$ studied by neutron scattering

Machteld E. Kamminga·Kristine M. L. Krighaar·Astrid T. Rømer·Lise Ø. Sandberg·Pascale P. Deen·Martin Boehm·G. D. Gu·J. M. Tranquada·Kim Lefmann
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Abstract

Here we present the effect of uniaxial stress on the magnetic stripes in the cuprate system La$_{2-x}$Ba$_{x}$CuO$_4$ with $x = 0.115$, previously found to have a stress-induced enhancement in the superconducting transition temperature. By means of neutron scattering, we show that the static stripes are suppressed by stress, pointing towards a trade-off between superconductivity and static magnetism, in direct agreement with previously reported $μ$SR measurements. Additionally, we show that some of the reduced weight in the elastic channel appears to have moved to the inelastic channel. Moreover, a stress-induced momentum shift of the fluctuations towards the typical 1/8 value of commensurability is observed. These results impose a strong constraint on the theoretical interpretation of stress-enhanced superconductivity in cuprate systems.

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Machteld E. Kamminga, Kristine M. L. Krighaar, Astrid T. Rømer, Lise Ø. Sandberg, Pascale P. Deen, Martin Boehm, G. D. Gu, J. M. Tranquada, Kim Lefmann. 2022-03-01. Evolution of magnetic stripes under uniaxial stress in La$_{1.885}$Ba$_{0.115}$CuO$_4$ studied by neutron scattering. https://doi.org/10.1103/physrevb.107.144506

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