题目：Doped Mott insulator and the implication for robust d-wave superconductivity in square lattice t-J model

报告人：朱伟 教授，西湖大学

时间：2021年5月8日上午10点

地点：国家脉冲强磁场科学中心C204

报告摘要：

Unravelling competing orders emergent in doped Mott insulators and their interplay with unconventional superconductivity is one of the major challenges in condensed matter physics. To explore possible superconductivity state in the doped Mott insulator, we study a square-lattice t-J model with both the nearest and next-nearest-neighbor electron hoppings and spin Heisenberg interactions. By using the state-of-the-art density matrix renormalization group simulations with imposing charge U(1) and spin SU(2) symmetries on the large-scale six-leg cylinders, we establish a quantum phase diagram including three phases: a stripe charge density wave phase,a superconducting phase without static charge order, and a superconducting phase coexistent with a weak charge stripe order. Crucially, we demonstrate that the superconducting phase has a power-law pairing correlation decaying much slower than the charge density and spin correlations, which is a quasi-1D descendant or the uniform d-wave superconductor in two dimensions. These findings reveal that enhanced charge and spin fluctuations with optimal doping is able to produce robust d-wave superconductivity in doped Mott insulators, providing a foundation for connecting theories of superconductivity to models of strongly correlated systems.

报告人简介：

朱伟教授2007年毕业于中国科学技术大学物理系并获得理学学士学位，2007年-2012年在中国科学技术大学合肥微尺度物质科学国家实验室攻读博士学位。2012年起，朱伟博士分别在美国加州州立大学北岭分校、普林斯顿大学、洛斯阿拉莫斯国家实验室从事博士后研究工作，主要研究强关联体系中的拓扑有序相、量子纠缠在多体物理中的应用等方向。2018年加入西湖大学。

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