Multicritical Fermi Surface Topological Transitions

Spin density wave order, topological order, and Fermi surface reconstruction

Hexagonally deformed Fermi surface of the 3D topological insulator Bi2Se3.

A hexagonal deformation of the Fermi surface of Bi2Se3 has been for the first time observed by angle-resolved photoemission spectroscopy. This is in contrast to the general belief that Bi2Se3 possesses an ideal Dirac cone. The hexagonal shape is found to disappear near the Dirac node, which would protect the surface state electrons from backscattering. It is also demonstrated that the Fermi ene...

Topological quantum phase transitions and edge states in spin-orbital coupled Fermi gases

We study superconducting states in the presence of spin-orbital coupling and Zeeman field. It is found that a phase transition from a Fulde-Ferrell-Larkin-Ovchinnikov state to the topological superconducting state occurs upon increasing the spin-orbital coupling. The nature of this topological phase transition and its critical property are investigated numerically. Physical properties of the to...

Thermodynamic signatures for topological phase transitions to Majorana and Weyl superfluids in ultracold Fermi gases

We discuss the thermodynamic signatures for the topological phase transitions into Majorana and Weyl superfluid phases in ultracold Fermi gases in two and three dimensions (2D and 3D) in the presence of Rashba spin-orbit coupling and a Zeeman field. We analyze the thermodynamic properties exhibiting the distinct nature of the topological phase transitions linked with the Majorana fermions (2D F...

Fermi liquid theory of electronic topological transitions and screening anomalies in metals

General expressions for the contributions of the Van Hove singularity (VHS) in the electron density of states to the thermodynamic potential Ω are obtained in the framework of a microscopic Fermi liquid theory. The renormalization of the singularities in Ω connected with the Lifshitz electronic topological transition (ETT) is found. Screening anomalies due to virtual transitions between VHS and...