Speaker: Costas Valagiannopoulos, Nazarbayev University
Title: Photonic Concepts Translated Into Quantum Arena
Abstract: A new funding landscape for quantum engineering research has been recently shaped comprising impressive state strategies like National Quantum Initiative Act that echoed extensive investments from industry giants like IBM, Google, Microsoft and Intel. Indeed, US Army Research Laboratory (ARL), Department of Defense (DoD), National Science Foundation (NSF) and Air Force Office of Scientific Research (AFOSR) have already approved numerous large-scale, multidisciplinary programs, most of them related to quantum interactions between particles and texture whose disruptive effects are behind a broad range of applications from quantum sensing and filtering to quantum circuits and memory.
From a fundamental point of view, the quantum side of any particle beam is described mostly by matter waves while the quantum texture by macroscopic quantities like the potential energy and the effective mass of the electrons therein. Given the fact that Schrodinger and Helmholtz equations look similar and wave functions and probability currents respect ordinary Dirichlet and Neumann boundary conditions, a direct analogy to Electromagnetics is formulated. Therefore, many photonic concepts can be translated into the quantum arena and reveal new dynamics and utilities that are useful in related applications.
In this talk, I will present certain cases that this translation is meaningful starting from super-scattering spherical inclusions made of realistic quantum media hosted in high-potential diamond environment that can work efficiently as sensors for the incoming beam energies. Furthermore, the well-known Fabry-Perot resonator will be investigated from the quantum point of view by focusing on its ability of selecting specific directions of the incident matter waves. The extreme angular selectivity in matter-wave tunneling will be demonstrated again with use of actual quantum materials and two different mechanisms of accomplishing it, will be identified. Finally, I will mention examples of optimally sharp planar filters for particle energies and quantum waveguides of maximal ability to get dissipatively coupled with external cavities.
Bio: Constantinos Valagiannopoulos (IEEE M’12, SM’16) was born in Athens, Greece, in 1982. He received the Dipl. Eng. (Hons.) degree in Electrical Engineering from the National Technical University of Athens, Greece, in 2004, and the Ph.D. degree on Electromagnetic Theory in 2009 from the same Institute. Between 2010 and 2014, he was a Postdoctoral Researcher in the Group of Theoretical and Applied Electromagnetics of Complex Media at Department of Electronics and Nanoengineering, Aalto University, Finland (advisor: Sergei Tretyakov). During the academic year 2014–2015, he was with the Laboratory of Metamaterials and Plasmonics at Department of Electrical and Computer Engineering, University of Texas at Austin, USA (advisor: Andrea Alu). From 2015, he is with Nazarbayev University (NU), Kazakhstan, as an Assistant and from 2018 as an Associate Professor in the Department of Physics. Meanwhile, he has been a visiting Assistant Professor at University of Southampton (Pavlos Lagoudakis group) and a visiting Scholar at Harvard University (Efthimios Kaxiras group). He currently leads the Metamaterials Modeling and Design Group at NU performing research on the forward and inverse design of photonic devices manipulating the light. He has authored or coauthored more than 90 works published at international refereed scientific journals and presented numerous reports in scientific conferences. He is currently participating as Principal Investigator (PI) or co-PI in the successful execution of national and international winning research grants with total annual budget more than 450K USD. Dr. Valagiannopoulos received the inaugural 2015 JOPT Research Excellence Award for his work: “Perfect absorption in graphene multilayers” and is a Senior Member of IEEE and OSA. He also received the International Chorafas Prize for the Best Doctoral Thesis in 2008, and the Academy of Finland Postdoctoral Grant for 2012–2015.