Time:  16:00 pm, 18th August, 2020

Speaker: Dr. Qisi Wang, University of Zurich, Switzerland

Abstract: 

High transition temperature (Tc) superconductivity in cuprate materials has been a subject of intense interest in condensed matter physics. Competing interactions in these materials lead to a rich phase diagram with intertwined spin, charge/orbital and lattice degrees of freedom. Unveiling the physical principles of such phases is critical for establishing the defining parameters of superconductivity. Resonant inelastic x-ray scattering (RIXS) is a powerful probe of multiple electronic correlations. With the tremendous improvement of energy resolution, RIXS has now revolutionized the study of elementary excitations in high-Tc materials. In this talk, I will present our recent progress using high-resolution RIXS to explore the interactions behind cuprate high-Tc superconductivity, including the works on (1) understanding the charge ordering in La-based cuprates from a unifying picture [1], and (2) revealing the origin of phonon anomaly in stripe-ordered cuprates [2].

[1] Q. Wang et al., Phys. Rev. Lett. 124, 187002 (2020).

[2] Q. Wang et al., unpublished.

Brief CV of Dr. Qisi Wang:

Dr. Qisi Wang obtained his PhD in condensed matter physics at Fudan University in 2018 under the supervision of Prof. Jun Zhao. Since then, he has been working as a postdoc researcher with Prof. Johan Chang at University of Zurich. He uses multiple scattering techniques including neutron scattering, resonant inelastic x-ray scattering and x-ray diffraction to investigate the quantum phases in correlated electron systems such as unconventional superconductors and frustrated magnets.

Click to view the recorded report video►http://as.iphy.ac.cn/video_detail.php?id=27608