Single Nanowire Photoconductive Terahertz Detectors

Abstract

Spectroscopy\nand imaging in the terahertz (THz) region of the electromagnetic spectrum\nhas proven to provide important insights in fields as diverse as chemical\nanalysis, materials characterization, security screening, and nondestructive\ntesting. However, compact optoelectronics suited to the most powerful\nterahertz technique, time-domain spectroscopy, are lacking. Here,\nwe implement single GaAs nanowires as microscopic coherent THz sensors\nand for the first time incorporated them into the pulsed time-domain\ntechnique. We also demonstrate the functionality of the single nanowire\nTHz detector as a spectrometer by using it to measure the transmission\nspectrum of a 290 GHz low pass filter. Thus, nanowires are shown to\nbe well suited for THz device applications and hold particular promise\nas near-field THz sensors.