Polarization-dependent photocurrents in polar stacks of van der Waals solids

Abstract

Monolayers of semiconducting van der Waals solids, such as transition metal dichalcogenides (TMDs), acquire significant electric polarization normal to the layers when placed on a substrate or in a heterogeneous stack. This causes linear coupling of electrons to electric fields normal to the layers. Irradiation at oblique incidence at frequencies above the gap causes interband transitions due to coupling to both normal and in-plane ac electric fields. The interference between the two processes leads to sizable in-plane photocurrents and valley currents. The direction and magnitude of currents is controlled by light polarization and is determined by its helical or non-helical components. The helicity-dependent ballistic current arises due to asymmetric photogeneration. The non-helical current has a ballistic contribution (dominant in sufficiently clean samples) caused by asymmetric scattering of photoexcited carriers, and a side-jump contribution. Magneto-induced photocurrent is due to the Lorentz force or due to intrinsic magnetic moment related to Berry curvature.

5 pages, 2 figures. Submitted to Physical Review Letters

References in corpus (10)

• Two Dimensional Atomic Crystals
• Van der Waals heterostructures
• Atomically thin p-n junctions with van der Waals heterointerfaces
• Intrinsic and Rashba Spin-orbit Interactions in Graphene Sheets
• k.p theory for two-dimensional transition metal dichalcogenide semiconductors
• Spin-orbit gap of graphene: First-principles calculations
• Detecting Topological Currents in Graphene Superlattices
• Generation and Electric Control of Spin-Coupled Valley Current in WSe2
• Optical generation and detection of pure valley current in monolayer transition metal dichalcogenides
• Enhanced photogalvanic effect in graphene due to Rashba spin-orbit coupling

Cited by in corpus (9)

• Photocurrents in Weyl semimetals
• Large bulk photovoltaic effect and spontaneous polarization of single-layer monochalcogenides
• Photogalvanic effect in Weyl semimetals
• High-frequency nonlinear transport and photogalvanic effects in two-dimensional topological insulators
• Spin-momentum locked interaction between guided photons and surface electrons in topological insulators
• Edge photogalvanic effect caused by optical alignment of carrier momenta in 2D Dirac materials
• Photovoltaic Hall effect in two-dimensional electron gas: Kinetic theory
• Photogalvanic currents in dynamically gapped Dirac materials
• Nonlinear optical responses in superconductors under magnetic fields: quantum geometry and topological superconductivity