Time：May 14 2021, 14:00-15:00

Venue: Room 526

Tencent Meeting ID: 311247181

Password：0514

Title：Unveiling the High-field Normal State of Cuprates with Charge and Spin Orders

Host：Jianhao Chen, Research Scientist (PI), BAQIS; Associate Professor International Center for Quantum Materials (ICQM), Peking University

Abstract：

The nature of the unconventional superconductivity (SC) in cuprates has been a long-standing puzzle. One of the central questions is to understand the normal state from which the SC originates. In this regard, high magnetic field has been commonly used to suppress SC and reveal the normal state. However, the strong SC in cuprates often preclude access to the normal state in the T=0 limit using experimentally available magnetic field. Moreover, the interplay of various competing orders in underdoped cuprates also plays a key role in determining the ground state and its effect is yet to be understood in the limit of high magnetic fields.

In this talk, I will discuss the main results of a series of experiments [1-3] performed using several complementary electrical transport techniques on underdoped La-214 cuprates where charge and spin orders form stripes near the 1/8 doping. Our results a) establish a robust vortex phase diagram for underdoped cuprates, b) provide much-needed transport signatures of the elusive pair-density wave state in stripe-ordered cuprates in high magnetic fields, and c) reveal striking, novel properties of the high-field normal state of cuprates. The implications of these results for cuprate research in general will also be discussed.

About the Speaker：

Zhenzhong Shi, Distinguished Professor of the School of Physics and Technology/Institute for Advanced Studies of Soochow University. Prof. Shi graduated from the Department of Modern Physics, University of Science and Technology of China in 2006. In 2013, he received a master's degree in electrical engineering and a doctorate degree in physics from the State University of New York at Buffalo. From 2013 to 2021, he was engaged in postdoctoral research at the National Laboratory for Strong Magnetic Fields in the United States and Duke University in the United States. His research focuses on a variety of quantum materials, including unconventional superconductors, quantum magnets, charge density wave materials, etc.