Improvement of the Electro-Optical Process in GaAs for Terahertz Single Pulse Detection by Using a Fiber-Coupling System

Adnan Haj Yahya,Avi Klein,Nezah Balal,Jacob Gerasimov,Aharon Friedman

doi:10.3390/app11156859

Abstract

The electro-optical process is a popular method for terahertz radiation detection. Detectors based on the electro-optical process have large bandwidth, and the signal-to-noise ratio (SNR) is relatively high. Further, this detector can be applied to detect high-power signals without using radiation attenuation. This paper presents a method to improve the electro-optic process to THz radiation detection based on GaAs crystals by coupling the optical output signal into fiber. Results demonstrated an improvement in the signal-to-noise ratio that means an increase in the dynamic range of the electro-optical detector.

Highlights

Terahertz (THz) technology has proven to be quite elusive; this is the electromagnetic spectrum of THz radiation situated between infrared light and microwave radiation
This paper presents an improvement of electro-optic detection of THz single pulse by Gallium Arsenide (GaAs) crystal by using a fiber coupling system
In order to perform an effective measurement of the THz pulse, a phase-matching condition is required, i.e, whether the phase-matching condition in GaAs crystal is obtained in 0.1 THz and 1550 nm wavelength

Summary

Introduction

Terahertz (THz) technology has proven to be quite elusive; this is the electromagnetic spectrum of THz radiation situated between infrared light and microwave radiation. Devices based on this wavelength are becoming increasingly important in a diversity of human activity applications [3,4], e.g., security, imaging, biological, communications, medicine, etc This led to the development of THz detection systems such as bolometers, which are essentially heat detectors [5]. There is a high priority to using THz detectors based on the free-space electro-optic process in nonlinear crystals [9]. This paper presents an improvement of electro-optic detection of THz single pulse by GaAs crystal by using a fiber coupling system. The preference for GaAs crystal is because of its detection frequency range, which reaches 6 THz. The coupling into fiber provides an easy way to increase the optic output signal, which can increase the dynamic range of the detector. The coupling of the optical output signal into fiber allows stretching the THz pulse, which can be done by using the electro-optic process to detect short THz pulses [15]

Methods

Results

Conclusion