Self-routing dual color nanosource based on the co-excitation via coupling between nano cavities

Abstract

Optical nano sources play important roles in optical communications, photonic integrated circuits, and quantum information. However, integratable, multi-color and directionally controllable nanoscale optical sources remain a challenge. This work presents a design of a two-channel upconversion nanosource based on phase coupling between metal-dielectric-metal (MDM) cavities. The resonant cavities embedded with upconversion nanoparticles (UCNPs) couple with each other by phase modulation in the bus waveguide, which enables simultaneous excitation and fluorescence enhancement of the UCNPs in cavities. Benefiting from inherent ability of MDM structure, the emitted light can be manipulated directionally for subsequent multi-channel applications. In addition, the relevant optical properties can be accurately described by a theoretical model. The excitation field strength in cavities was found to be sensitive to the coupling phase, and the derived theoretical model can predict the optimal coupling distance for an efficient dual-channel upconversion nano-emitter. This nano-emitter combines the unique fluorescence advantages of UCNPs with the easy preparation of MDM nanocavities for easy integration and nanoscale optical control, promising major applications in photonic chips, optical sensors, and complex energy optoelectronic devices.

Keywords

• Nanoemitters
• Surface plasmon polaritons
• Metal-Dielectric-Metal cavities
• Lanthanide-doped upconversion nanoparticles