Sadakov Andrey V, Vlasenko Vladimir A, Troyan Ivan A, Sobolevskiy Oleg A, Semenok Dmitrii V, Zhou Di, Pudalov Vladimir M
P. N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow 119991, Russia.
Shubnikov Institute of Crystallography, Federal Scientific Research Center Crystallography and Photonics, Russian Academy of Sciences, 59 Leninsky Prospekt, Moscow 119333, Russia.
J Phys Chem Lett. 2023 Jul 27;14(29):6666-6671. doi: 10.1021/acs.jpclett.3c01577. Epub 2023 Jul 18.
A comprehensive study of vortex phases and vortex dynamics is presented for a recently discovered high-temperature superconductor YH with (onset) of 215 K under a pressure of 200 GPa. The thermal activation energy () is derived within the framework of the thermally activated flux flow (TAFF) theory. The activation energy yields a power law dependence ∝ on magnetic field with a possible crossover at a field around 8-10 T. Furthermore, we have depicted the vortex phase transition from the vortex-glass to vortex-liquid state according to the vortex-glass theory. Finally, vortex phase diagram is constructed for the first time for superhydrides. Very high estimated values of flux flow barriers () = (1.5-7) × 10 K together with high crossover fields make YH a rather outstanding superconductor as compared to most cuprates and iron-based systems. The Ginzburg number for YH = (3-7) × 10 indicates that thermal fluctuations are not so strong and cannot broaden superconducting transitions in weak magnetic fields.
本文对最近发现的高温超导体YH进行了涡旋相和涡旋动力学的综合研究，该超导体在200 GPa压力下的（起始）温度为215 K。热激活能（）是在热激活磁通流（TAFF）理论框架内推导得出的。激活能在磁场中呈现出幂律依赖关系 ∝ ，在约8 - 10 T的磁场处可能存在交叉。此外，根据涡旋玻璃理论，我们描绘了从涡旋玻璃到涡旋液态的涡旋相变。最后，首次为超氢化物构建了涡旋相图。与大多数铜酸盐和铁基体系相比，极高的磁通流势垒估计值（） = （1.5 - 7）× 10 K以及高交叉场使得YH成为一种相当出色的超导体。YH的金兹堡数 = （3 - 7）× 10表明热涨落不是很强，不会在弱磁场中拓宽超导转变。
