时间：2022年7月12日（周二） 14:00-15:30

Time: 14:00-15:30, Tuesday, July 12th, 2022

主持人: 西湖大学理学院PI 吴颉 博士

Host: Dr. Jie Wu, PI of School of Science, Westlake University

地点：西湖大学云栖校区5号楼一楼学术报告厅

Venue: Lecture Hall, 1st Floor, Building 5, Yunqi Campus

主讲嘉宾/Speaker：

金魁 教授

中国科学院物理研究所

主讲人简介/Biography:

Kui Jin is a group leader (since 2013) and the deputy director (since 2017) of National Lab for Superconductivity in Institute of Physics (IOP), Chinese Academy of Sciences (CAS). He also leads a CAS Interdisciplinary Innovation Team on High-throughput Superconductivity Research since 2018, and serves as the chief scientist of both the Key-Area R&D Program of Guangdong Province (since 2020) and the National Key R&D Program of China (since 2021). He has been awarded the 5th Sir Martin Wood China Prize, and the Young Scientist Prize of Chinese Academy of Sciences in 2021. Jin and his team have been devoted to investigating the mechanism of high-temperature superconductivity and relevant key scientific issues in practical applications.

讲座摘要/Abstract:

Soon after the discovery of cuprate superconductors, the strange-metal behavior of their normal-state resistivity was observed, namely, a linear resistivity as a function of temperature (T-linear resistivity) persisting much lower than the Debye temperature. About one decade ago, several groups [1-3] unveiled an intimated correlation between the superconducting transition temperature (T_c) and the slope of the T-linear resistivity (A₁). That is, these two quantities increase or decrease simultaneously. Consequently, the question the community has been after is: what connects the strength of superconductivity with electron scattering? To solve this issue, one needs to quantify the relationship between T_c and A₁. However, it turns out to be a great challenge to manipulate external parameters for marked evolution of properties with minute changes. In this talk, I would like to share with you two pieces of our recent work [4,5] and report on the discovery of T_c ~ A₁^0.5 relationship in different families of high-temperature superconductors. For a cuprate system La_2-xCe_xCuO₄, we developed advanced high-throughput techniques and used a combinatorial library to map how superconducting properties and normal-state properties of the superconductor evolve with minute compositional variation (Δx) with unprecedented resolution and accuracy [4]. We also achieved continuous evolution of superconductivity in ion-gated FeSe film via electric-field gating technique integrated with two-coil mutual inductance and electrical transport property measurements [5]. Such relationship between T_c and A₁ is at work for both systems, yet different techniques were employed to tune the superconductivity minutely. Remarkably, the scaling is seemingly satisfied also in hole-doped cuprate, as well as a class of organic superconductors via pressure tuning. This unexpected universal scale indicates that there is perhaps a common origin of superconductivity in unconventional superconductors.

[1] Cooper et al. Science 323,603 (2009)

[2] Taillefer Annu. Rev. Condens. Matter Phys. 1,51 (2010)

[3] Jin et al. Nature 476,73 (2011)

[4] Yuan et al. Nature 602,431 (2022)

[5] Jiang et al. Nature Phys. under revision

讲座联系人/Contact:

理学院 钟老师 zhongmengzhen@westlake.edu.cn