Time:1101201 (Wed.) 14:20~16:20
Speaker:Prof. 仲崇厚(CHUNG, Chung-Hou)
國立陽明交通大學電子物理學系/Department of Electrophysics, National Yang Ming Chiao Tung University
Title:有趣的量子多體物理系統The fascinating quantum many-body physics
Abstract:Over the recent decades, there are many surprising new quantum phenomena in condensed matter systems that cannot be understood in terms of single particle pictures. Well-known examples include: high-temperature superconductivity in cuprates, Kondo effect in quantum impurity systems, spin-liquid in magnetic materials, strange metal non-Fermi liquid behaviors. The underling mechanism behind these phenomena is the strong electron correlations (Coulomb interactions), which leads to collective many-body phenomena. In this talk, I will introduce the basics of these phenomena and the theoretical approaches to account for these emergent quantum phenomena. In particular, I will focus on the mechanism of non-Fermi liquid “strange metal” phenomena in various rare-earth intermetallic compounds near magnetic phase transitions, characterized by quasi-linear-in-T resistivity and T-logarithmic specific heat coefficient at low temperatures [1][2][3]. We find competition between short-ranged anti-ferromagnetic spin-liquid state and the fluctuating Kondo correlations provide an excellent qualitative understanding of these strange metal states.
[1] Strange metal state near a heavy-fermion quantum, Yung-Yeh Chang, Silke Paschen, Chung-Hou Chung*, critical point, Phys. Rev. B 97, 035156 (2018).
[2] Strange superconductivity near an antiferromagnetic heavy fermion quantum critical point, Y. Y. Chang, F. Hsu, S. Kirchner, C. Y. Mou, T. K. Lee, C. H. Chung*, Phys. Rev. B 99, 094513 (2019)
[3] Strange metal in paramagnetic heavy-fermion Kondo lattice: Dynamical large-N fermionic multi-channel approach, Jiangfan Wang, Yung-Yeh Chang, Chung-Hou Chung, arXiv:2005.03427 (PNAS submitted and under revision)
Place:B101, Gongquan Campuses, NTNU |