Sr$_2$RuO$_4$中多极涨落减慢的超声观测
Ultrasonic Observation of Slowing Down of Multipole Fluctuations in Sr$_2$RuO$_4$
AI总结：
通过超声测量研究非常规超导体Sr$_2$RuO$_4$在超导转变温度附近的电子态动力学，观测到面内横向超声衰减系数增大，并发现与多极自由度相关的涨落减慢现象，提出电十六极起关键作用。
摘要：
我们对非常规超导体Sr$_2$RuO$_4$进行了超声测量，以研究其超导转变温度$T_\mathrm{c} = 1.4$ K附近电子态的动力学性质。我们观察到，随着温度接近$T_\mathrm{c}$，面内横向超声衰减系数增大。超声衰减表现出Landau-Khalatnikov型超声频率依赖性，典型弛豫时间约为$10^{-10}$ s。在施加10 T磁场下，超导转变被抑制。然而，超声衰减系数在低温下仍增大，表明与多极自由度相关的涨落减慢。基于群论考虑，我们提出电十六极在减慢过程中起关键作用。此外，我们讨论了多分量超导序参量与多极自由度之间的关系。
英文摘要：
We performed ultrasonic measurements on the unconventional superconductor Sr$_2$RuO$_4$ to investigate the dynamical properties of the electronic states near its superconducting transition temperature, $T_\mathrm{c} = 1.4$ K. We observed an increase in the in-plane transverse ultrasonic attenuation coefficient as the temperature approached $T_\mathrm{c}$. The ultrasonic attenuation exhibited a Landau-Khalatnikov-type ultrasonic frequency dependence with a typical relaxation time of approximately $10^{-10}$ s. Under an applied magnetic field of 10 T, the superconducting transition was suppressed. However, the ultrasonic attenuation coefficient exhibited an increase down to low temperatures, indicating the slowing down of fluctuations associated with multipole degrees of freedom. Based on group-theoretical considerations, we propose that the electric hexadecapole plays a crucial role in the slowing down. Furthermore, we discuss the relationship between multi-component superconducting order parameters and multipole degrees of freedom.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
