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arXiv · 2206.14499

Doping dependence of the upper critical field in untwinned YBa$_2$Cu$_3$O$_{7-\delta}$ thin films

E. Wahlberg·R. Arpaia·A. Kalaboukhov·T. Bauch·F. Lombardi
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Abstract

We report on measurements of the doping dependence of the upper critical field $H_{c,2}$ in 50 nm thick YBa$_2$Cu$_3$O$_{7-\delta}$ films. The films are untwinned and are characterized by a small in-plane compressive strain. We find that the $H_{c,2}$ shows a strong decrease in the underdoped region of the phase diagram, in agreement with what has been measured in relaxed single crystals. The origin of the decrease of $H_{c,2}$ in the underdoped regime is discussed within a scenario where charge density wave order competes with superconductivity. This demonstrates the potential of using thin films for studying the phase diagram of high-$T_c$ materials under strain.

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E. Wahlberg, R. Arpaia, A. Kalaboukhov, T. Bauch, F. Lombardi. 2022-06-29. Doping dependence of the upper critical field in untwinned YBa$_2$Cu$_3$O$_{7-\delta}$ thin films. https://doi.org/10.1088/1361-6668%2Faca93b

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