Slow light in a 2D semiconductor plasmonic structure.

Spectrally narrow optical resonances can be used to generate slow light, i.e., a large reduction in the group velocity.

Localized interlayer excitons in MoSe-WSe heterostructures without a moiré potential.

Interlayer excitons (IXs) in MoSe-WSe heterobilayers have generated interest as highly tunable light emitters in transition metal dichalcogenide (TMD) heterostructures. Previous reports of spectrally narrow (<1 meV) photoluminescence (PL) emission lines at low temperature have been attributed to IXs localized by the moiré potential between the TMD layers. We show that spectrally narrow IX PL lines are present even when the moiré potential is suppressed by inserting a bilayer hexagonal boron nitride (hBN) spacer between the TMD layers.

Interlayer Exciton Diode and Transistor.

Controlling the flow of charge neutral interlayer exciton (IX) quasiparticles can potentially lead to low loss excitonic circuits. Here, we report unidirectional transport of IXs along nanoscale electrostatically defined channels in an MoSe-WSe heterostructure. These results are enabled by a lithographically defined triangular etch in a graphene gate to create a potential energy "slide".

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.