Magneto-reflection spectroscopy of monolayer transition-metal dichalcogenide semiconductors in pulsed magnetic fields

Abstract

We describe recent experimental efforts to perform polarization-resolved optical spectroscopy of monolayer transition-metal dichalcogenide semiconductors in very large pulsed magnetic fields to 65 tesla. The experimental setup and technical challenges are discussed in detail, and temperature-dependent magneto-reflection spectra from atomically thin tungsten disulphide (WS${}_2$) are presented. The data clearly reveal not only the valley Zeeman effect in these 2D semiconductors, but also the small quadratic exciton diamagnetic shift from which the very small exciton size can be directly inferred. Finally, we present model calculations that demonstrate how the measured diamagnetic shifts can be used to constrain estimates of the exciton binding energy in this new family of monolayer semiconductors.

PCSI-43 conference (Jan. 2016; Palm Springs, CA)

References in corpus (16)

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• Magneto-spectroscopy of Highly-Aligned Carbon Nanotubes: Identifying the Role of Threading Magnetic Flux

Cited by in corpus (6)

• Probing the influence of dielectric environment on excitons in monolayer WSe2: Insight from high magnetic fields
• Excitonic valley effects in monolayer WS${}_2$ under high magnetic fields
• Probing Many-Body Interactions in Monolayer Transition-Metal Dichalcogenides
• Monolayer transition metal dichalcogenides in strong magnetic fields: Validating the Wannier model using a microscopic calculation
• Superradiant coupling effects in transition-metal dichalcogenides
• Proximity-enhanced valley Zeeman splitting at the WS${}_2$/graphene interface