Articulo
Microscopic theory of the nematic phase in Sr₃Ru₂O₇
Registro en:
issn:1098-0121
issn:1550-235X
Autor
Raghu, Srinivas
Paramekanti, Arun
Kim, Eun Ah
Borzi, Rodolfo Alberto
Grigera, Santiago Andrés
Mackenzie, Andrew P.
Kivelson, Steve
Institución
Resumen
In an externally applied magnetic field, ultrapure crystals of the bilayer compound Sr₃Ru₂O₇ undergo a metamagnetic transition below a critical temperature, T*, which varies as a function of the angle between the magnetic field H and the Ru-O planes. Moreover, T* approaches zero when H is perpendicular to the planes. This putative "metamagnetic quantum critical point," however, is pre-empted by a nematic fluid phase with order one resistive anisotropy in the ab plane. In a "realistic" bilayer model with moderate strength local Coulomb interactions, the existence of a sharp divergence of the electronic density of states near a van Hove singularity of the quasi-one-dimensional bands, and the presence of spin-orbit coupling results in a mean-field phase diagram which accounts for many of these experimentally observed phenomena. Although the spin-orbit coupling is not overly strong, it destroys the otherwise near-perfect Fermi-surface nesting and hence suppresses spin-density-wave ordering. Facultad de Ciencias Exactas Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas Instituto de Física La Plata Instituto de Física de Líquidos y Sistemas Biológicos