Switchable Giant Bulk Photocurrents and Photo-spin-currents in Monolayer PT-symmetric Anti-ferromagnet MnPSe3

Abstract: Converting light into steady currents and spin-currents in two-dimensional (2D) platform is essential for future energy harvesting and spintronics. We show that the giant and modulable bulk photovoltaic effects (BPVEs) can be achieved in air-stable 2D antiferromagnet (AFM) monolayer MnPSe3, with nonlinear photoconductance > 4000 nm$\cdot\mu$A/V2 and photo-spin-conductance > 2000 (nm$\cdot\mu$A/V2 $\hbar$/2e) in the visible spectrum. The propagation and the spin-polarizations of photocurrents can be switched via simply rotating the N$\'e$el vector. We unveil that the PT-symmetry, mirror symmetries, and spin-orbital-couplings are the keys for the observed sizable and controllable 2D BPVEs. All the results provide insights into the BPVEs of 2D AFM, and suggest that the layered MnPSe3 is an outstanding 2D platform for energy device and photo-spintronics.