Camjayi A, Acha C, Weht R, Rodríguez M G, Corraze B, Janod E, Cario L, Rozenberg M J
Departamento de Física, FCEN, UBA, and IFIBA, CONICET, Pabellón 1, Ciudad Universitaria, 1428 Buenos Aires, Argentina.
Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica (CNEA), Avenida General Paz y Constituyentes, 1650 San Martín, Argentina and Instituto Sábato, Universidad Nacional de San Martín-CNEA, 1650 San Martín, Argentina.
Phys Rev Lett. 2014 Aug 22;113(8):086404. doi: 10.1103/PhysRevLett.113.086404. Epub 2014 Aug 21.
The nature of the Mott transition in the absence of any symmetry breaking remains a matter of debate. We study the correlation-driven insulator-to-metal transition in the prototypical 3D Mott system GaTa(4)Se(8), as a function of temperature and applied pressure. We report novel experiments on single crystals, which demonstrate that the transition is of first order and follows from the coexistence of two states, one insulating and one metallic, that we toggle with a small bias current. We provide support for our findings by contrasting the experimental data with calculations that combine local density approximation with dynamical mean-field theory, which are in very good agreement.
在不存在任何对称性破缺的情况下，莫特转变的本质仍是一个有争议的问题。我们研究了典型的三维莫特体系GaTa(4)Se(8)中由关联驱动的绝缘体到金属的转变，它是温度和外加压力的函数。我们报告了对单晶的新实验，这些实验表明该转变是一级的，且源于两种状态的共存，一种是绝缘态，一种是金属态，我们能用一个小的偏置电流在两者之间切换。我们通过将实验数据与结合了局域密度近似和动力学平均场理论的计算结果进行对比，为我们的发现提供了支持，二者吻合得非常好。
