Imaging dynamic exciton interactions and coupling in transition metal dichalcogenides

Abstract

Transition metal dichalcogenides (TMDs) are regarded as a possible materials platform for quantum information science and related device applications. In TMD monolayers, the dephasing time and inhomogeneity are crucial parameters for any quantum information application. In TMD heterostructures, coupling strength and interlayer exciton lifetimes are also parameters of interest. However, many demonstrations in TMDs can only be realized at specific spots on the sample, presenting a challenge to the scalability of these applications. Here, using multi-dimensional coherent imaging spectroscopy (MDCIS), we shed light on the underlying physics - including dephasing, inhomogeneity, and strain - for a MoSe${}_2$ monolayer and identify both promising and unfavorable areas for quantum information applications. We furthermore apply the same technique to a MoSe${}_2$/WSe${}_2$ heterostructure. Despite the notable presence of strain and dielectric environment changes, coherent and incoherent coupling, as well as interlayer exciton lifetimes are mostly robust across the sample. This uniformity is despite a significantly inhomogeneous interlayer exciton photoluminescence distribution that suggests a bad sample for device applications. This robustness strengthens the case for TMDs as a next-generation materials platform in quantum information science and beyond.

References in corpus (8)

• Ultrafast Charge Transfer in Atomically Thin MoS2/WS2 Heterostructures
• Observation of Long-Lived Interlayer Excitons in Monolayer MoSe2-WSe2 Heterostructures
• Determination of band alignment in the single layer MoS2/WSe2 heterojunction
• Interlayer Exciton Optoelectronics in a 2D Heterostructure p-n Junction
• Probing the inter-layer exciton physics in a MoS${}_2$/MoSe${}_2$/MoS${}_2$ van der Waals heterostructure
• Ultrafast charge-transfer dynamics in twisted MoS${}_2$/WSe${}_2$ heterostructures
• Fundamental exciton linewidth broadening in monolayer transition metal dichalcogenides
• Coherent exciton-exciton interactions and exciton dynamics in a MoSe\textsubscript{2}/WSe\textsubscript{2} heterostructure

Cited by in corpus (2)

• Exciton lifetime and optical linewidth profile via exciton-phonon interactions: Theory and first-principles calculations for monolayer MoS${}_2$
• Rapid multiplex ultrafast nonlinear microscopy for material characterization