Efficient surface second-harmonic generation in slot micro/nano-fibers

TL;DR

This paper demonstrates that slot micro/nano-fibers significantly enhance surface second-harmonic generation, offering a promising platform for ultra-tiny light sources across a broad spectrum.

Contribution

It introduces a novel slot fiber design that boosts second-harmonic generation efficiency using surface dipole nonlinearity, with high manufacturability.

Findings

Maximum conversion efficiency is about 24 times higher than circular fibers.

Slot structure enhances light confinement and surface area.

Potential for fiber-based light sources from UV to mid-infrared.

Abstract

We propose to use slot micro/nano-fiber (SMNF) to enhance the second-harmonic generation based on surface dipole nonlinearity. The slot structure is simple and promising to manufacture with high accuracy and reliability by mature micromachining techniques. Light field can be enhanced and confined, and the surface area can be increased in the sub-wavelength low-refractive-index air slot. The maximum conversion efficiency of the SMNFs in our calculations is about 24 times higher than that of circular micro/nano-fibers. It is promising to provide a competing platform for a new class of fiber-based ultra-tiny light sources spanning the UV- to the mid-infrared spectrum.