paper

Time reversal symmetry breaking and -wave superconductivity of triple-point fermions

arXiv:2105.07568 · doi:10.1103/PhysRevB.104.134512

Abstract

We study the possibility of complex tensor (-wave) superconducting order in three-dimensional semimetals with chiral spin-1/2 triple-point fermions, which have an effective orbital angular momentum of arising from a crossing of three bands. Retaining the first three lowest order terms in momentum and assuming rotational symmetry we show that the resulting mean-field -wave ground state breaks time reversal symmetry, and depends crucially on the coefficients of the two quadratic terms in the Hamiltonian. The phase diagram at a finite chemical potential displays both the "cyclic" and the "ferromagnetic" states, distinguished by the average value of the magnetization; in the former state it is minimal (zero), whereas in the latter it is maximal (two). In both states we find mini Bogoliubov-Fermi surfaces in the quasiparticle spectrum, conforming to recent general arguments.

12 pages, 3 figures; minor changes, additional comments and references, close to published version

References in corpus (8)

Cited by in corpus (4)