Optical Signature of Bias-Induced Carrier Injection in a WSe2/MoS2 Heterostructure Diode

Abstract

We investigate the bias-dependent photoluminescence (PL) response of a WSe${}_2$/MoS${}_2$ heterostructure diode. Under forward bias, trion-related emission in WSe${}_2$ is markedly enhanced, whereas reverse bias produces minimal spectral changes. This asymmetric response cannot be explained by electric-field effects alone and instead reflects carrier injection at the functional interface. These results demonstrate that PL provides a direct optical probe of carrier injection in an operating van der Waals heterostructure. More broadly, this approach establishes spatially resolved PL spectroscopy as a versatile tool for pinpointing the interfaces governing device operation in van der Waals heterostructures.

References in corpus (13)

• Atomically thin MoS2: A new direct-gap semiconductor
• Observation of tightly bound trions in monolayer MoS2
• Observation of Long-Lived Interlayer Excitons in Monolayer MoSe2-WSe2 Heterostructures
• Electrical Control of Two-Dimensional Neutral and Charged Excitons in a Monolayer Semiconductor
• Optical Generation of Excitonic Valley Coherence in Monolayer WSe2
• Strong interlayer coupling in van der Waals heterostructures built from single-layer chalcogenides
• Electroluminescence and photocurrent generation from atomically sharp WSe2/MoS2 heterojunction p-n diodes
• Photovoltaic effect in an electrically tunable van der Waals heterojunction
• Determination of band alignment in the single layer MoS2/WSe2 heterojunction
• Bright excitons in monolayer transition metal dichalcogenides: from Dirac cones to Dirac saddle points
• Interlayer Exciton Optoelectronics in a 2D Heterostructure p-n Junction
• Momentum-space indirect interlayer excitons in transition metal dichalcogenide van der Waals heterostructures
• Ultrafast charge-transfer dynamics in twisted MoS${}_2$/WSe${}_2$ heterostructures