Nonreciprocal Transport in 2D Halide Perovskite

Inversion symmetry breaking is an enabling factor behind many emergent phenomena. 2D halide perovskites with low dimensionality and variable crystalline structure emerged as promising candidates for manipulating symmetry, while probing the symmetry change and corresponding effects due to fine structural modulation can be obscured. Here we report the observation of nonreciprocal transport and nonlinear optical effects in 2D halide perovskite. The measured results resulting from inversion symmetry breaking could be reproduced by calculations based on a tight-binding model, which highlighted the quantum geometric origin with dominant contribution from multiband process. We anticipate that such unique low-dimensional systems will provide fertile ground for engineering crystal symmetry and discovering novel optoelectronic functionalities.