Year: 2020
Type: article
Abstract: We explore a spin-fermion model with fermion-spin-quadrupolar interaction. In a nematic phase, this interaction reduces to a four-fermion interaction that is the basis of superconductivity. When the coupling constant is positive the superconductivity is a p -wave with spin-parallel–paired fermions. When it is negative the superconductivity is a p -wave and fermions are spin-antiparallel paired. For a system with zero chemical potential, even a very small coupling can bind fermions into a bound state that leads to superconductivity. When the chemical potential is non-zero the system possesses quantum critical transition from the normal spin-nematic phase to the phase where superconductivity coexists with spin-nematicity. The value of the quantum critical fermion-spin-nematicity coupling constant depends on the chemical potential.
Source: Europhysics Letters (EPL)
Author: Naoum Karchev
Institution: Sofia University "St. Kliment Ohridski"
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2964388075