Solid State & Optics Seminar
sponsored by “The Flint Fund Series on Quantum Devices and Nanostructures”
Date : Wednesday, 5/3/23
Time: 1:00 PM
Dr. Wei-Sheng Lee, Stanford Institute of Materials and Energy Sciences
Location: Mason 107 or via Zoom
Zoom Link: https://yale.zoom.us/j/99362515138?pwd=cGZnejY0YWUrRkpmSlpTT0RwOVhYZz09
Password: 459071
RIXS Studies on Charge Order Phenomena in Cuprate and Nickelate Superconductors
The role of charge order (CO) in unconventional superconductors is an intriguing and extensively studied research topic. Further insight could be gained by simultaneously tracking the CO order parameter and its excitations in the phase diagram. In this talk, I will highlight our recent high resolution resonant inelastic x-ray scattering (RIXS) studies on the CO phenomena in double-layered cuprates Bi2Sr2CaCu2O8+d, where signatures of CO excitations can be identified in the RIXS phonon cross-section [1]. Interestingly, anomalous enhancements of the CO excitations deep inside the superconducting state were observed near optimal doping, despite the suppression of the CO order parameter [2]. By tracking this anomalous temperature dependence throughout the phase diagram, we identify a characteristic doping concentration of the CO phenomena [3] and discuss its implications on putative quantum critical points. If time permits, I will also talk about our recent discovery of CO in infinite-layer nickelate superconductors [4] and discuss the similarities and differences to the CO in cuprates.
[1] L. Chaix, G. Ghiringhelli, Y. Y. Peng, M. Hashimoto, B. Moritz, K. Kummer, N. Brookes, Y. He, S. Chen, S. Ishida, Y. Yoshida, H. Eisaki, L. Braicovich, Z.-X. Shen, T. P. Devereaux, W.-S. Lee, Dispersive Charge Density Wave Excitations in Underdoped Cuprates Bi2Sr2CaCu2O8+d. Nature Physics 13, 952 (2017).
[2] W. S. Lee, K. J. Zhou, M. Hepting, J. Li, A. Nag, A. C. Walters, M. Garcia-Fernandez, H. Robarts, M. Hashimoto, H. Lu, B. Nosarzewski, D. Song, H. Eisaki, Z. X. Shen, B. Moritz, J. Zaanen, T. P. Devereaux, Spectroscopic Fingerprint of Charge Order Melting via Quantum Fluctuations in a Cuprate, Nature Physics 17, 659 (2021).
[3] H. Lu, M. Hashimoto, S. Chen, S. Ishida, D. Song, H. Eisaki, A. Nag, M Garcia-Fernandez, R. Arpaia, G. Ghiringhelli, L. Braicovich, J. Zaanen, B. Moritz, K. Kummer, N. B. Brookes, K.-J. Zhou, Z.-X. Shen, T. P. Devereaux, and W.-S. Lee, Identification of a Characteristic Doping for Charge Order phenomena in Bi-2212 cuprates via RIXS, Phys. Rev. B 106, 155109 (2022).
[4] M. Rossi, M. Osada, J. Choi, S. Agrestini, D. Jost, Y. Lee, H. Lu, B. Y. Wang, K. Lee, A. Nag, Y. D. Chuang, C. T. Kuo, S. J. Lee, B. Moritz, T. P. Devereaux, Z.X. Shen, J.S. Lee, K.-J. Zhou, H. Y. Hwang and W.S. Lee, A Broken Translational Symmetry State in an Infinite-Layer Nickelate, Nature Physics 18, 869 (2022).
Host: Yu He