Prof. Mauro Fernandes Pereira obtained his PhD at the Optical Sciences Center, University of Arizona and has given important contributions to Nonequlibrium Greens Functions (NEGF) Many Body Theory of Transport and Optics of Semiconductor Materials. His research combines fundamental Mathematical Physics with applications to device development, with an impact in medicine and the environment, with a current emphasis on the protection of water critical infrastructures.
He has been named SPIE Fellow in 2011 for his contributions to the Theory of Semiconductor Materials and Optics.
He created the TERA-MIR concept unifying THz and Mid Infrared Radiation and was the Chair of COST ACTION MP1204: TERA-MIR Radiation: Materials, Generation, Detection and Applications and Chair of the Series of NATO TERA-MIR Conferences (2009, 2012, 2015 and 2018). He coordinates the TERA-MIR Network (http://www.tera-mir.org).
He has been awarded the SPIE Innovation Awards in Quantum Sensing and Nano Electronics and Photonics (2019) for contributions to science and his service through organizing NATO TERA-MIR and COST.
He was a research associate at CBPF, Uni-Rostock and TU-Berlin, a visiting Lecturer at Uni-Bremen, Senior Researcher at Tyndall Institute, Professor and Chair of Theory of Semiconductor Materials and Optics at Sheffield Hallam University and Head of the Department of Condensed Matter Theory at the Institute of Physics of the Academy of Sciences of Czech Republic, before joining KU as Professor and Chair of the Physics Department.
GHz-THz nonlinear optics in semiconductor superlattices
Optical nonlinearities are of perpetual importance, notably connected with emerging new materials. Achieving a strong nonlinear response in the microwave to far-infrared spectral ranges is important for the development of GHz-THz technologies e.g. for noninvasive screening medical applications. Nonlinearities in semiconductors are well understood in near infrared and visible ranges, but little is known about the nonlinear response in the GHz and THz regime. Our aim is to deliver a state of the art simulator of intersubband transport and optical response of superlattices, based on Nonequilibrium Green’s Functions calculations, coupled with exact solutions of the corresponding Boltzmann equation. This will enable us to design structures with large nonlinear response controlled by external parameters. Prospective structures will be fabricated by Molecular Beam Epitaxy and characterized using spectroscopic, electrical transmission electrical microcopy and electron tomography measurements, thus providing a feedback for the simulator development. We will gain a deep understanding of microscopic phenomena underlying the nonlinearities and provide guidelines for designing components with application potential, such as frequency multipliers. The resulting optimized devices will be used in a spectrometer developed by our collaborators for breath analysis, which is a noninvasive medical screening applications with strong potential for early detection of respiratory diseases such as covid-19, before it becomes symptomatic. The resulting devices also have potential for water quality control. Water masks the sensitive spectroscopic detection of most dangerous substances and we will design our multipliers to operate in one the few GHz-THz low absorption windows of the water spectrum.
Quantum Cascade Laser and Detector Simulator
The project involves development of software tools to design and simulate the behaviour of quantum cascade lasers (QCL's) working in terahertz and mid-infrared frequencies. The first QCL was constructed in 1994, and have significant advantages over conventional interband-based diode lasers. From a QCL the laser power generated can be up to 1000x greater, also QCLs can be manufactured to produce laser light over a wide range of frequencies not accessible to interband emitters. Applications of Terahertz emissions are now being heavily researched, as there are many possible applications. The most striking is within medical diagnostics, as THz emissions are non-ionising and non-radioactive, and therefore safer than X-rays and other forms of imaging. THz light can penetrate organic material to a depth of several cm and is absorbed in proportion to the water content of the organic matter or organ, and can be used to identify early stage tumours, gases within the body that indicate the presence of disease. Initial devices for imaging of teeth are being introduced, as an alternative to dental X-rays. Beyond medical applications, THz devices have potential to be used for explosive detection, and for "radar" type devices within cars, and there are many other potential applications. Many universities and companies in the world are working on medical diagnostic technology using THz imaging and QCLs. Current laser simulation tools, which can reduce drastically the price of development of new devices, are not capable of simulating QCL’s. The underlying physics is a lot more complex then in conventional lasers; most designers do not understand it. This project will lead to a user-friendly simulator, full of visual capabilities that will allow anyone with minimum physics understanding to design a QCL without necessarily knowing the complex underlying physics.
PhD Student Fellowships for the projects: Quantum Cascade Laser and Detector Simulator; GHz-THz Nonlinear Optics in Semiconductor Superlattices