Finite-momentum superconductivity from chiral bands in twisted MoTe2
摘要
A recent experiment has reported unconventional superconductivity in twisted bilayer MoTe2, emerging from a normal state that exhibits a finite anomalous Hall effect – a signature of intrinsic chirality. Motivated by this discovery, we construct a continuum model for twisted MoTe2 constrained by lattice symmetries from first-principles calculations that captures the moiré-induced inversion symmetry breaking even in the absence of a displacement field. Building on this model, we show that overscreening of the nominally repulsive Coulomb interaction gives rise to finite-momentum superconductivity in this chiral moiré system. Remarkably, the finite-momentum superconducting state can arise solely from internal symmetry breaking of the moiré superlattice, differentiating it from previously studied cases that require external fields. It further features a nonreciprocal quasiparticle dispersion and an intrinsic superconducting diode effect. Our results highlight a novel route to unconventional superconducting states in twisted transition metal dichalcogenides moiré systems, driven entirely by intrinsic symmetry-breaking effects.