Physics Seminar
Nanostructured Materials for Optoelectronic Applications and Quantum Technologies
Speaker: Johann Peter Reithmaier (Universität Kassel)
Date: Wednesday 27 April 2022
Time: 15:00
Venue: Zoom
Material properties can be strongly modified by the geometric dimensions of nanosized substructures, such as quantum dots embedded in a semiconductor matrix. This allows to engineer the optical gain spectrum for different application targets. Examples will be given for temperature stabilized wavelengths in GaAs-based high-power QD lasers as well as for InP-based QD-lasers for optical communication. Here the impact of atom-like gain profiles on laser properties, such as temperature stability, modulation speed and emission linewidth, will be discussed. In the talk, also a brief overview on other activities of the group will be given, which includes among others, the realization of 1.55 μm single photon emission in cavity enhanced single QD emitters for fiber-based quantum communication and color centers in diamond nanostructures as material platform for quantum technology applications, such as quantum computing or sensing.
Short bio: Prof. Johann Peter Reithmaier studied physics at TU Munich and made his PhD at Siemens and Walter-Schottky-Institute in 1990. Until 1992, he worked as Postdoc at IBM in Rüschlikon, Switzerland on III/V epitaxy. In 1992, he joined University of Würzburg where he built-up a research group working on nanostructured semiconductors and their applications in optoelectronic devices. In 2005 he became a full professor of physics and director of the Institute of Nanostructure Technologies and Analytics at the University of Kassel. He is author or co-author of more than 800 journal and conference papers (> 365 in refereed journals, 2 books, 10 book articles and > 145 invited talks, > 14,500 citations), He is a member of the Deutsche Physikalische Gesellschaft (DPG) and of IEEE Photonics Society. He became Fellow of IEEE in 2011. From 2014 to 2020, he was co-editor of OPTICA. He was and is on the advisory board of different national centers (EPSRC National Centre for III-V Technologies in UK 2010-2016, Centre of Nanophotonics for Terabit Communications (NATEC) in Denmark since 2016) and since 2021 Technical Advisory Board of EPSRC research consortium 'QUantum Dot On Silicon systems for communications, information processing and sensing' (QUDOS), UK. Since 2016, he is speaker of the Center of Interdisciplinary Nanostructure Science and Technology (CINSaT) of University of Kassel. Since 2018, he is coordinator of the LOEWE priority project SMolBits (Scalable Molecular Quantum Bits). His current interests are focused on nanostructured semiconductors and their optoelectronic applications. This includes self-assembly techniques of III-V quantum dot materials on GaAs, InP and Si substrates as well as nanostructuring by high-resolution lithographical techniques. New types of devices are investigated like nanolasers, single photon sources, ultra-high speed and narrow linewidth lasers, high power lasers, light emitting devices on silicon and nanocrystalline diamond for biomedical, quantum computing and quantum communication applications.