Macroscopic transition metal dichalcogenides monolayers with uniformly high optical quality.

The unique optical properties of transition metal dichalcogenide (TMD) monolayers have attracted significant attention for both photonics applications and fundamental studies of low-dimensional systems. TMD monolayers of high optical quality, however, have been limited to micron-sized flakes produced by low-throughput and labour-intensive processes, whereas large-area films are often affected by surface defects and large inhomogeneity. Here we report a rapid and reliable method to synthesize macroscopic-scale TMD monolayers of uniform, high optical quality.

Imaging dynamic exciton interactions and coupling in transition metal dichalcogenides.

Transition metal dichalcogenides (TMDs) are regarded as a possible material 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.

Nanoscale Trapping of Interlayer Excitons in a 2D Semiconductor Heterostructure.

For quantum technologies based on single excitons and spins, the deterministic placement and control of a single exciton is a longstanding goal. MoSe-WSe heterostructures host spatially indirect interlayer excitons (IXs) that exhibit highly tunable energies and unique spin-valley physics, making them promising candidates for quantum information processing. Previous IX trapping approaches involving moiré superlattices and nanopillars do not meet the quantum technology requirements of deterministic placement and energy tunability.

2D semiconductor nonlinear plasmonic modulators.

A plasmonic modulator is a device that controls the amplitude or phase of propagating plasmons. In a pure plasmonic modulator, the presence or absence of a plasmonic pump wave controls the amplitude of a plasmonic probe wave through a channel. This control has to be mediated by an interaction between disparate plasmonic waves, typically requiring the integration of a nonlinear material.