Far infrared (THz) Electroluminescence from Si/SiGe Quantum Cascade Heterostructures

Lynch, S.A., Paul, D.P. , Bates, R., Norris, D.J., Cullis, A.G., Ikonic, Z., Kelsall, R.W., Harrison, P., Arnone, D.D. and Pidgeon, C.R. (2003) Far infrared (THz) Electroluminescence from Si/SiGe Quantum Cascade Heterostructures. In: Opto-Ireland 2002: Optics and Photonics Technologies and Applications, Galway, Ireland, 5-6 Septmber 2002, pp. 140-149. (doi: 10.1117/12.463738)

Abstract

There is strong interest in the development of sources that emit radiation in the far infrared (1-10 THz) frequency range for applications which include early detection of skin cancer, dental imaging, telecommunications, security scanning, gas sensing, astronomy, molecular spectroscopy, and the possible detection of biological weapons. While a number of THz sources are available, there are at present no compact, efficient, cheap and practical high-power solid-state sources such as light emitting diodes or lasers. Silicon is an excellent candidate for such a THz source since the lack of polar optical phonon scattering makes it an inherently low loss material at these frequencies. Furthermore, since over 97% of all microelectronics is presently silicon based, the realisation of a silicon based emitter/laser could potentially allow integration with conventional silicon-based microelectronics. In this paper THz electroluminescence from a Si/SiGe quantum cascade structure operating significantly above liquid helium temperatures is demonstrated. Fourier transform infrared spectroscopy was performed using step scan spectrometer with a liquid helium cooled Si-bolometer for detection. Spectra are presented demonstrating intersubband electroluminescence at a number of different frequencies. These spectral features agree very well with the theoretically calculated intersubband transitions predicted for the structure.

• Item Type: Conference Proceedings
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Paul, Professor Douglas
• Authors: Lynch, S.A., Paul, D.P., Bates, R., Norris, D.J., Cullis, A.G., Ikonic, Z., Kelsall, R.W., Harrison, P., Arnone, D.D., and Pidgeon, C.R.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Research Group: Semiconductor Devices