Tunable quantum metric driven nonlinear valley Hall effect in the -symmetric sliding antiferroelectric
Phys. Rev. B 113, 235116 – Published 9 June, 2026
DOI: https://doi.org/10.1103/p9sb-k9fj
Abstract
The quantum metric, the real part of a quantum geometric tensor, plays an important role in fundamental transport and optical responses of quantum materials. While net quantum metric effects are typically realized by breaking both time-reversal () and inversion () symmetries, valley-contrast mechanisms enable the probing of quantum geometry in centrosymmetric, nonmagnetic systems, revealing physical signatures beyond Berry curvature. Here, we design a four-layer platform that combines sliding antiferroelectric order with strain-induced breaking to realize a quantum metric driven nonlinear valley Hall effect (NVHE) under preserved and symmetries. Reversible interlayer sliding () provides nonvolatile electrical control of the valley response. First-principles calculations reveal an outer-layer-dominated NVHE with tunable sign and magnitude. This symmetry-preserving, sliding-tunable strategy activates hidden quantum geometric phenomena in realistic two-dimensional materials and opens a clean pathway for tunable valleytronics and quantum information devices.