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Updated: Jul 17, 2026

Radio Frequency Magnetron Sputtering of GdBa2Cu3O7−δ/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 (STO) Single-crystal Substrates
Published on: April 12, 2019
Composite to tilted vortex lattice transition in Bi2Sr2CaCu2O8+delta in oblique fields
M Konczykowski1, C J van der Beek, A E Koshelev
1Laboratoire des Solides Irradiés, CNRS-UMR 7642 & CEA/DSM/DRECAM, Ecole Polytechnique, Palaiseau, France.
Abstract:
Precision measurements of the vortex phase diagram in single crystals of the layered superconductor Bi2Sr2CaCu2O8+delta in oblique magnetic fields confirm the existence of a second phase transition, in addition to the usual first-order vortex-lattice melting line Hm(T). The transition has a strong first-order character, is accompanied by strong hysteresis, and intersects the melting line in a tricritical point (Hm perpendicular, Hcr parallel). Its field dependence and the changing character of the melting line at the tricritical point strongly suggest that the ground state for magnetic fields closely aligned with the superconducting layers is a lattice of uniformly tilted vortex lines.
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