Electric field controlled valley-polarized photocurrent switch based on the circular bulk photovoltaic effect

Abstract

Efficient electric manipulation of valley degrees of freedom is critical and challenging for the advancement of valley-based information science and technology. We put forth an electrical scheme, based on a two-band Dirac model, that can switch the fully valley-polarized photocurrent between K and K' valleys using the circular bulk electro-photovoltaic effect. This is accomplished by applying an out-of-plane electric field to the two-dimensional valley materials, which enables continuous tuning of the Berry curvature and its sign flip. We found that the switch of the fully valley-polarized photocurrent is directly tied to the sign change of Berry curvature, which accompanies a topological phase transition, for instance, the quantum spin Hall effect and the quantum valley Hall effect. This scheme has been confirmed in monolayer BiAsI2 and germanene through first-principles calculations. Our paper offers a promising strategy for the development of a volatile valley-addressable memory device and could inspire further research in this area.

References in corpus (13)

• Valley polarization in MoS2 monolayers by optical pumping
• The Valley Hall Effect in MoS2 Transistors
• Valley filter and valley valve in graphene
• Valley Dependent Optoelectronics from Inversion Symmetry Breaking
• Valley-Polarized Metals and Quantum Anomalous Hall Effect in Silicene
• Valley Splitting and Polarization by the Zeeman Effect in Monolayer MoSe2
• Generation and Electric Control of Spin-Coupled Valley Current in WSe2
• Opto-Valleytronic Spin Injection in Monolayer MoS2/Few-Layer Graphene Hybrid Spin Valves
• Gate tunable giant anisotropic resistance in ultra-thin GaTe
• Sign-reversible valley-dependent Berry phase effects in 2D valley-half-semiconductors
• Nanostructured graphene for spintronics
• Transmission spectra and valley processing of graphene and carbon nanotube superlattices with inter-valley coupling
• Realization of valley-spin polarized current via parametric pump in monolayer $\mathrm{Mo}{\mathrm{S}}_2$