Directional terahertz emission from diffusion-engineered InAs structures

TL;DR

This paper presents a novel InAs-based terahertz emitter with surface-normal radiation achieved through diffusion engineering and patterning, enhancing directional emission control for THz applications.

Contribution

The authors designed and fabricated a new THz emitter with directional surface-normal emission using corrugated patterns on InAs, demonstrating control over emission efficiency.

Findings

Directional THz emission achieved along surface-normal

Emission efficiency controlled by pattern width

Corrugated mirror patterns enhance radiation directionality

Abstract

We have designed and fabricated a new type of terahertz (THz) emitter that radiates THz waves along the surface-normal direction because of the lateral distributions of the transient electric dipoles. The excitation and measurements were performed using a conventional THz time-domain spectroscopy scheme with femtosecond optical pulses. The corrugated mirror patterns on the InAs layers made the radiation directional along the surface-normal direction, and the emission efficiency was controlled by adjustment of the pattern width.