Liu Wei, Punnoose Alexander
Physics Department, City College of the City University of New York, New York, New York 10031, USA.
Instituto de Física Teórica - Universidade Estadual Paulista, R. Dr. Bento Teobaldo Ferraz 271, Barra Funda, São Paulo, São Paulo 01140-070, Brazil.
Phys Rev Lett. 2015 May 1;114(17):176402. doi: 10.1103/PhysRevLett.114.176402. Epub 2015 Apr 30.
Phase transitions involving spontaneous time-reversal symmetry breaking are studied on the honeycomb lattice at finite hole doping with next-nearest-neighbor repulsion. We derive an exact expression for the mean-field equation of state in closed form, valid at temperatures much less than the Fermi energy. Contrary to standard expectations, we find that thermally induced intraband particle-hole excitations can create and stabilize a uniform metallic phase with broken time-reversal symmetry as the temperature is raised in a region where the ground state is a trivial metal.
在具有次近邻排斥作用的有限空穴掺杂蜂窝晶格上，研究了涉及自发时间反演对称性破缺的相变。我们推导出了状态平均场方程的精确闭合形式表达式，该表达式在温度远低于费米能时有效。与标准预期相反，我们发现，在基态为平凡金属的区域中，随着温度升高，热诱导的带内粒子 - 空穴激发可以产生并稳定具有破缺时间反演对称性的均匀金属相。
