Deterministic coupling of site-controlled quantum emitters in monolayer WSe to plasmonic nanocavities.

Solid-state single-quantum emitters are crucial resources for on-chip photonic quantum technologies and require efficient cavity-emitter coupling to realize quantum networks beyond the single-node level. Monolayer WSe, a transition metal dichalcogenide semiconductor, can host randomly located quantum emitters, while nanobubbles as well as lithographically defined arrays of pillars in contact with the transition metal dichalcogenide act as spatially controlled stressors. The induced strain can then create excitons at defined locations.

Trion-Species-Resolved Quantum Beats in MoSe.

Monolayer photonic materials offer a tremendous potential for on-chip optoelectronic devices. Their realization requires knowledge of optical coherence properties of excitons and trions that have so far been limited to nonlinear optical experiments carried out with strongly inhomogeneously broadened material. Here we employ h-BN-encapsulated and electrically gated MoSe to reveal coherence properties of trion species directly in the linear optical response.

Nonmagnetic Quantum Emitters in Boron Nitride with Ultranarrow and Sideband-Free Emission Spectra.

Hexagonal boron nitride (hBN) is an emerging material in nanophotonics and an attractive host for color centers for quantum photonic devices. Here, we show that optical emission from individual quantum emitters in hBN is spatially correlated with structural defects and can display ultranarrow zero-phonon line width down to 45 μeV if spectral diffusion is effectively eliminated by proper surface passivation. We demonstrate that undesired emission into phonon sidebands is largely absent for this type of emitter.

Strong Acoustic Phonon Localization in Copolymer-Wrapped Carbon Nanotubes.

Understanding and controlling exciton-phonon interactions in carbon nanotubes has important implications for producing efficient nanophotonic devices. Here we show that laser vaporization-grown carbon nanotubes display ultranarrow luminescence line widths (120 μeV) and well-resolved acoustic phonon sidebands at low temperatures when dispersed with a polyfluorene copolymer. Remarkably, we do not observe a correlation of the zero-phonon line width with (13)C atomic concentration, as would be expected for pure dephasing of excitons with acoustic phonons.