||電気系E3棟2階 会議室B E3-215
"Sensing with Quantum Cascade Laser and Detector Systems"
Optical sensors for mid-infrared spectroscopy are widely used in industrial and environmental monitoring as well as medical and biochemical diagnostics. A sensor concept, based on a bi-functional quantum cascade heterostructure, for which the differentiation between laser and detector is eliminated, enables mutual commutation of laser and detector, simplifies remote sensing setups and facilitates a crucial miniaturization of sensing devices.
Liquid sensing utilizing bi-functional quantum cascade lasers/detectors (QCLDs) can be realized on a single chip. A QCL active region design with an additional detection capability at the laser emission wavelength allows a straightforward integration, where different parts of the chip are used for lasers and others for detectors. The performance of such bi-functional designs has been optimized to reach a similar laser performance as conventional QCLs, allowing for high duty cycle operation at room temperature.
Typical analyte interaction lengths for gas sensing are in the range of tens of centimeters or more and exceed the common semiconductor chip sizes. Our gas sensing approach incorporates surface-active lasers and detectors. The latest demonstrator consists of two concentric ring QCLDs with second order distributed feedback (DFB) gratings on top of the waveguides. These DFB gratings facilitate vertical light emission and detection in the biased lasing and unbiased detector configuration, respectively. The two rings emit at two different wavelengths, which provides room temperature lasing and detection of two wavelengths monolithically integrated on the same chip.
Erich Gornik received his Ph.D. degree in Physics in 1972. He was a Postdoctoral Fellow at Bell Laboratories, Holmdel, USA, from 1975 to1977. In 1979, he has been appointed Professor for Experimental Physics at the University of Innsbruck. In 1988, he became Professor for Semiconductor Physics and Director at the Walter Schottky Institute of the Technical University Munich. From 1993 until 2012, he was Full Professor for Semiconductor Electronics and Director of the Micro-and Nanostructure Center (ZMNS) at the Technical University of Vienna and since then he is emeritus Professor. From 2003 to 2008 he was managing director of the Austrian Research Centers.
He has spent several Research Professorships at numerous international research institutions and has received various awards; among others, he is Fellow of the American Physical Society since 1995. In 1997 he received the “Wittgenstein Preis” of the Austrian Government and in 2000 the “Erwin Schrödinger Preis” of the Austrian Academy of Science. He has supervised more than 150 Master and PhD students. Further achievements are 540-refereed publications, 90 invited and plenary lectures at international conferences.