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arXiv · 2008.11527

Nature of the magnetic stripes in fully oxygenated La$_{2}$CuO$_{4+y}$

Ana-Elena Tutueanu·Henrik Jacobsen·Pia Jensen Ray·Sonja Holm-Dahlin·Monica-Elisabeta Lacatusu·Tim Birger Tejsner·Jean-Claude Grivel·Wolfgang Schmidt·Rasmus Toft-Petersen·Paul Steffens·Martin Boehm·Barrett Wells·Linda Udby·Kim Lefmann·Astrid Tranum Rømer
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Abstract

We present triple-axis neutron scattering studies of static and dynamic magnetic stripes in an optimally oxygen-doped cuprate superconductor, La$_{2}$CuO$_{4+y}$, which exhibits a clean superconducting transition at $T_{\rm c}=42$ K. Polarization analysis reveals that the magnetic stripe structure is equally represented along both of the tetragonal crystal axes and that the fluctuating stripes display significant weight for in-plane as well as out-of-plane spin components. Both static magnetic order as well as low-energy fluctuations are fully developed in zero applied magnetic field and the low-energy spin fluctuations at $\hbar ω= 0.3-10$ meV intensify upon cooling. We interpret this as an indication that superconductivity and low-energy spin fluctuations co-exist microscopically in spatial regions which are separated from domains with static magnetic order.

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Ana-Elena Tutueanu, Henrik Jacobsen, Pia Jensen Ray, Sonja Holm-Dahlin, Monica-Elisabeta Lacatusu, Tim Birger Tejsner, Jean-Claude Grivel, Wolfgang Schmidt, Rasmus Toft-Petersen, Paul Steffens, Martin Boehm, Barrett Wells, Linda Udby, Kim Lefmann, Astrid Tranum Rømer. 2020-08-26. Nature of the magnetic stripes in fully oxygenated La$_{2}$CuO$_{4+y}$. https://doi.org/10.1103/physrevb.103.045138

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