Quasi-two-dimensional vortex matter in the ThH10 superhydride

Physical Review B: Condensed Matter and Materials Physics. 2024. Vol. 109. No. 22. Article 224515.

Sadakov A., Vlasenko V., Semenok D., Zhou D., Troyan I., Usoltsev A., Pudalov V.

A comprehensive study of the vortex phases and vortex dynamics is presented for a recently discovered hightemperature superconductor ThH10 with T_C = 153K at 170 GPa. The obtained results strongly suggest a quasitwo-dimensional (2D) character of the vortex-glass phase transition in ThH10. The activation energy yields a
logarithmic dependence U_0 ∝ ln(H) on magnetic field in a low-field region and a power-law dependence U_0 ∼
H^{−1} in a high-field region, signaling a crossover from 2D regime to three-dimensional collective pinning regime,
respectively. Additionally, a pinning force-field dependence showcases dominance of surface-type pinning in the
vicinity of T_C. Thermal activation energy (U0 ), derived within thermally activated flux-flow theory, takes very
high values above 2 × 10^5 K together with the Ginzburg number Gi = 0.039–0.085, which is lower only than
those of BiSrCaCuO cuprates and 10–3–8 family of iron-based superconductor. This indicates the enormous role
of thermal fluctuations in the dynamics of the vortex lattice of superhydrides, the physics of which is similar to
the physics of iron-based and copper-based high-temperature superconductors.

Keywords: high temperature superconductors, высокотемпературные сверхпроводники, Abrikosov vortices, Абрикосовские вихри, superhydrides, супергидриды