We examine the low-temperature states supported by the quasiperiodic host-guest structure of elemental bismuth at high pressure, Bi-III. Our electronic transport and magnetization experiments establish Bi-III as a rare example of type II superconductivity in an element, with a record upper critical field of ~ 2.5 T, unusually strong electron-phonon coupling, and an anomalously large, linear temperature dependence of the electrical resistivity in the normal state. These properties may be attributed to the peculiar phonon spectrum of incommensurate host-guest structures, which exhibit additional quasi-acoustic sliding modes, suggesting a pathway toward strong coupling superconductivity with the potential for enhanced transition temperatures and high critical fields.

中文翻译：

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准周期主客体结构中的强耦合超导性。

我们研究了在Bi-III高压下铋的准周期主客体结构所支持的低温状态。我们的电子传输和磁化实验确定Bi-III是元素中II型超导的罕见例子，其记录的最高临界场约为2.5 T，电子-声子耦合异常强，并且异常大的线性温度依赖性正常状态下的电阻率。这些性质可能归因于不相称的宿主-客体结构的特殊声子谱，它们表现出额外的准声滑动模式，这暗示了通向强耦合超导的途径，具有提高转变温度和高临界场的潜力。