Speaker
Aaron Dunbrack
(University of Jyväskylä)
Description
Typically, the connection between quantum geometry and flat-band superconductivity is derived in the presence of time-reversal symmetry. In the absence of both time-reversal and inversion, it is possible to have a term in the free energy that is linear in phase gradient (called the Lifshitz invariant); this term gives rise to a helical modulation of the superconducting order parameter. In a flat band, this term is dependent on "mixed quantum geometry" that combines k-space and parameter-space.