Colloquium----Institute of Theoretical Physics，Chinese Academy of Sciences

Institute of Theoretical Physics
Chinese Academy of Sciences
State Key Laboratory of Theoretical Physics
Colloquium

Title 题目	The Strong Correlation Problem in the “Standard Model”-From Brinkman-Rice to Mott Metal-Insulator Transitions,Slater to Fractionalized Magnetism, and Spin Liquids to High Temperature Superconductivity
Speaker 报告人	Ziqiang Wang
Affiliation 所在单位	Boston College
Date 日期	3:00pm Jan.8, 2015( Thursday)
Venue 地点	ITP new building 6620
Abstract 摘要	Over the past 50 years, fundamental progress has been made in understanding the many-body properties of correlated electron materials that have represented both the challenge and the vitality of condensed matter physics. In this talk, we discuss some of the most basic and essential properties of the strong correlation problem from the perspectives of the “standard” model – the Hubbard model – and the transition metal oxide high-Tc superconductors. Guided by a new, analytical solution of the Hubbard model on the Bethe lattice that goes beyond the dynamical mean field theory, we show that the binding between doublon (doubly occupied sites) and holon (empty sites) governs the incoherent Mott-Hubbard excitations and plays a key role in the Mott transition from a strongly renormalized metallic phase with Brinkman-Rice-Gutzwiller coherent quasiparticles to an insulating quantum spin liquid with gapless spinon excitations. A generic phase structure emerges on bipartite lattices at half-filling, where the ground states exhibit a continuous transition from a paramagnetic metal to an antiferromagnetic (AF) Slater insulator with coherent quasiparticles followed by a Mott transition into an incoherent, electron-fractionalized AF∗ phase. We argue that doublon-holon binding unites the three important ideas of strong correlation: coherent quasiparticles, incoherent Hubbard bands, and the spin-charge deconfined Mott insulator.

Contact Person

所内合作者

Sen Zhou(周森)