Clamp-Tapering Increases the Quality Factor of Stressed Nanobeams.

Stressed nanomechanical resonators are known to have exceptionally high quality factors ( Q) due to the dilution of intrinsic dissipation by stress. Typically, the amount of dissipation dilution and thus the resonator Q is limited by the high mode curvature region near the clamps. Here we study the effect of clamp geometry on the Q of nanobeams made of high-stress SiN.

Excitonic Emission of Monolayer Semiconductors Near-Field Coupled to High-Q Microresonators.

We present quantum yield measurements of single layer WSe (1L-WSe) integrated with high-Q ( Q > 10) optical microdisk cavities, using an efficient (η > 90%) near-field coupling scheme based on a tapered optical fiber. Coupling of the excitonic emission is achieved by placing 1L-WSe in the evanescent cavity field. This preserves the microresonator high intrinsic quality factor ( Q > 10) below the bandgap of 1L-WSe.

Enhanced detection limit by dark mode perturbation in 2D photonic crystal slab refractive index sensors.

We demonstrate for the first time a 300nm thick, 300μm × 300μm 2D dielectric photonic crystal slab membrane with a quality factor of 10,600 by coupling light to slightly perturbed dark modes through alternating nano-hole sizes. The newly created fundamental guided resonances greatly reduce nano-fabrication accuracy requirements. Moreover, we created a new layer architecture resulting in electric field enhancement at the interface between the slab and sensing regions, and spectral sensitivity of >800 nm/RIU, that is, >0.