Terahertz asymmetric quantum well infrared photodetector design based on electromagnetically induced transparency
Ali Rostami, M. Zyaei, H. Rasooli Saghai +1 more
A new Terahertz photodetector based on Electromagnetically Induced Transparency (EIT) is proposed. In the terahertz range (low energy signal) the limiting point is dark current. Dark current determines the signal-noise ratio of detectors. Our main purpose in terahertz detection is reduction of the dark current which is done by converting the incoming Terahertz IR signal to short-wavelength or visible probe optical field through EIT phenomena. For realization of this idea, we used 4-level atoms which can be implemented by quantum wells or dots. In the proposed structure, the terahertz-IR signal does not interact directly with ground state electrons, but affects the absorption characteristics of the short-wavelength or visible probe optical field that directly interact with ground state electrons. Therefore, in the proposed structure, the important thermionic dark current in terahertz detection, can be strongly reduced.
Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 6, 2008•2 citations