Doping-dependent competition between superconductivity and polycrystalline charge density waves

S. Caprara; M. Grilli; J. Lorenzana; B. Leridon

doi:10.21468/scipostphys.8.1.003

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arXiv · 1908.03408

Doping-dependent competition between superconductivity and polycrystalline charge density waves

S. Caprara·M. Grilli·J. Lorenzana·B. Leridon

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Abstract

From systematic analysis of the high pulsed magnetic field resistance data of La$_{2-x}$Sr$_x$CuO$_{4}$ thin films, we extract an experimental phase diagram for several doping values ranging from the very underdoped to the very overdoped regimes. Our analysis highlights a competition between charge density waves and superconductivity which is ubiquitous between $x=0.08$ and $x=0.19$ and produces the previously observed double step transition. When suppressed by a strong magnetic field, superconductivity is resilient for two specific doping ranges centered around respectively $x\approx 0.09$ and $x\approx 0.19$ and the characteristic temperature for the onset of the competing charge density wave phase is found to vanish above $x = 0.19$. At $x=1/8$ the two phases are found to coexist exactly at zero magnetic field.

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S. Caprara, M. Grilli, J. Lorenzana, B. Leridon. 2019-08-09. Doping-dependent competition between superconductivity and polycrystalline charge density waves. https://doi.org/10.21468/scipostphys.8.1.003

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