近日，上海高压科学技术先进研究中心的Viktor V Struzhkin及其研究小组取得一项新进展。经过不懈努力，他们提出研究金刚石压砧中新型超导氢化物的磁法。相关研究成果已于2024年1月5日在国际知名学术期刊《国家科学评论》上发表。

在这篇前瞻性文章中，研究人员将简要概述四种不同技术在金刚石压砧(DAC)中探测磁场排出和迈斯纳状态的结果。金刚石压砧是唯一能在超高压环境下研究高Tc超导氢化物的高压容器。

据悉，近年来，人们见证了高压实验中发现高T_c氢化物的巨大成功。这是通过与元素周期表上的其他元素制造金属氢“合金”来实现的。虽然Neil Aschcroft提出的最初想法是使用合金来降低生产纯金属氢所需的压力，但稳定这些氢化物所需的压力仍然很高，以至于很难获得磁场完全排出(迈斯纳状态)的原位测量，这是超导的一个定义特征。这种缺陷在迈斯纳效应研究中引发了对新型氢化物超导性主张的多重质疑，并激发了新的技术发展以应对这些挑战。

附：英文原文

Title: Magnetic Methods in Studies of New Superconducting Hydrides in a Diamond Anvil Cell

Author: Struzhkin, Viktor V, Mao, Ho-kwang

Issue&Volume: 2024-01-05

Abstract: In recent years, we witnessed a great success in discoveries of the high-Tc hydrides in high pressure experiments. This was achieved by creating metallic hydrogen ‘alloys’ with other elements across the periodic table. Although the original idea suggested by Neil Aschcroft [1] was to use alloying to reduce the pressure required for producing pure metallic hydrogen, the pressures required to stabilize these hydrides are still so high that in-situ measurements of the complete expulsion of the magnetic field (the Meissner state), a defining character of superconductivity, is difficult to obtain. Such deficit of the Meissner effect studies has provoked multiple critiques on claims of superconductivity in these new hydride materials, and stimulated new technical developments to meet these challenges. In this perspective article, we will provide a short summary of the results obtained with four alternative techniques which were used to probe the magnetic field expulsion and the Meissner state in a diamond-avnvil cell (DAC), which is the only high-pressure vessel capable of studying the high T_c superconducting hydrides at very high pressures.

DOI: 10.1093/nsr/nwae005

Source: https://dx.doi.org/10.1093/nsr/nwae005