Large and tunable photo-thermoelectric effect in single-layer MoS2

Abstract

We study the photoresponse of single-layer MoS2 field-effect transistors by scanning photocurrent microscopy. We find that, unlike in many other semiconductors, the photocurrent generation in single-layer MoS2 is dominated by the photo-thermoelectric effect and not by the separation of photoexcited electron-hole pairs across the Schottky barriers at the MoS2/electrode interfaces. We observe a large value for the Seebeck coefficient for single-layer MoS2 that, by an external electric field, can be tuned between -4x10^2 uV/K and -1x10^5 uV/K. This large and tunable Seebeck coefficient of the single-layer MoS2 paves the way to new applications of this material such as on-chip thermopower generation and waste thermal energy harvesting.

Supporting information included

References in corpus (6)

• Electric Field Effect in Atomically Thin Carbon Films
• Two Dimensional Atomic Crystals
• Anomalous Lattice Vibrations of Single and Few-Layer MoS2
• Elastic properties of freely suspended MoS2 nanosheets
• Laser-thinning of MoS2: on demand generation of a single-layer semiconductor
• Optical identification of atomically thin dichalcogenide crystals

Cited by in corpus (8)

• Phonon and Raman scattering of two-dimensional transition metal dichalcogenides from monolayer, multilayer to bulk material
• Photocurrent generation with two-dimensional van der Waals semiconductors
• Photovoltaic and photothermoelectric effect in a double-gated WSe2 device
• Large Thermoelectricity via Variable Range Hopping in Chemical Vapor Deposition Grown Single-layer MoS2
• Investigation of Band-Offsets at Monolayer-Multilayer MoS2 Junctions by Scanning Photocurrent Microscopy
• Newly observed first-order resonant Raman modes in few-layer MoS${}_2$
• Hot-electron cooling by acoustic and optical phonons in monolayers of MoS${}_2$ and other transition-metal dichalcogenides
• Photoinduced quantum spin and valley Hall effects and orbital magnetization in monolayer MoS2