Progress In Electromagnetics Research B

ROOM TEMPERATURE TERAHERTZ PHOTODETECTION IN ATOMIC AND QUANTUM WELL REALIZED STRUCTURES

M. Zyaei, Aly Rostami, Hamed Haji Khanmohamadi, H. Rasooli Saghai

Published Jan 1, 2011• 4 citations

Abstract

Abstract—A novel kind of room temperature terahertz photodetector based on Electromagnetically Induced Transparency (EIT) is presented. The main idea for room temperature and THz range operation is reduction of dark current which is done by converting of the incoming terahertz signal (long-wavelength Infrared signal) to shortwavelength field through EIT phenomena. For realization of this idea, we examine EIT phenomena in multi levels atomic system and quantum wells cascade structures. In the proposed structure the quantum interference between long wavelength and short-wavelength radiation modifies the absorption characteristic of short-wavelength probe field. By this means, the terahertz signal does not interact directly with ground state electrons, but affects on the absorption characteristics of

DOI: 10.2528/pierb10121502

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