[PC2] Cuprates, Novel materials

3:45 PM - 4:15 PM JST(6:45 AM - 7:15 AM UTC)

[PC2-03-INV] Orbital FF/LO Phases in NbSe2 Multilayers

*Jianting Ye¹ (1. University of Groningen (Netherlands))

Keywords:

Layered Superconductors,FFLO

Recent advances in two-dimensional materials have opened new avenues for exploring unconventional superconductivity in engineered multilayers. Among them, transition metal dichalcogenides (TMDs), such as NbSe₂, offer a unique platform to investigate Ising superconductivity and quantum phase transitions under strong spin-orbit coupling. In this talk, I will show that a Fulde–Ferrell–Larkin–Ovchinnikov (FFLO) state arises from Josephson coupling between adjacent superconducting layers, enabling the formation of finite-momentum pairing states. I will present evidence for orbital Fulde–Ferrell (FF) and Larkin–Ovchinnikov (LO) states in multilayer NbSe₂, where field-tunable inversion symmetry breaking emerges spontaneously within an otherwise globally centrosymmetric system. These FF/LO phases exhibit characteristic signatures in nonreciprocal transport: the FF state shows nonreciprocal vortex dynamics and Berezinskii–Kosterlitz–Thouless (BKT) criticality near phase boundaries, along with strongly anisotropic current–voltage (I–V) characteristics. Our findings reveal that inversion symmetry breaking can be a dynamic and emergent property of finite-momentum condensates, offering a new pathway to polar superconductivity and exotic collective behavior in 2D quantum systems.