Abstract: Considering the enormous advances in nanometer-scale CMOS technology that now allows one to reliably fabricate billions of switching devices on a single silicon die, electrostatically controlled quantum dots appear to be promising candidates for a batch implementation of quantum bits (qubits) and quantum logic circuits in order to facilitate mass production of quantum computers. This talk introduces the concept of semiconductor qubits and discusses the feasibility of such qubits from the point of view of quantum information and from the point of view of practical implementation.
We begin by explaining the idea of classic and quantum bits of information and highlighting the difference between the two. We then show what quantum systems can be qualified as qubits. Using the framework of the Schrodinger formalism, we develop a theoretical approach and simulation techniques to understand the behaviour of electrons injected in quantum dots, and, hence, the dynamics of semiconductor qubits. We introduce the fidelity of a semiconductor qubit and construct its Bloch sphere. Finally, we conclude the talk by presenting a discussion on universal quantum gates realised through such semiconductor qubits.
Bio: Dr. Elena Blokhina received the Habilitation HDR (D.Sc.) degree in electronic engineering from UPMC Sorbonne Universities, France, in 2017, a Ph.D. degree in physical and mathematical sciences and an M.Sc. degree in physics from Saratov State University, Russia, in 2006 and 2002 respectively. Since 2007, she has been with the School of Electrical and Electronic Engineering of University College Dublin, Ireland, and is currently a lecturer and the coordinator of the Circuits and Systems Research Group. Dr Blokhina is a Senior member of IEEE and the Chair Elect of the IEEE Technical Committee on Nonlinear Circuits and Systems. She had been elected to serve as a member of the Boards of Governors of the IEEE Circuits and Systems Society (CAS) for the term 2013-2015 and has been re-elected for the term 2015-2017. She has served as a member of organising committees, review and programme committee, session chair and track chair at many international conferences on electronics, circuits and systems and nonlinear physics including as IEEE International Symposium on Circuits and Systems (ISCAS), IEEE Latin American Symposium on Circuits and Systems (LASCAS), IEEE Asia-Pacific Conference on Circuits and Systems (APCCAS), International Symposium on Nonlinear Theory and Its Applications (NOLTA), IEEE international Conference on Electronics, Circuits and Systems (ICECS) and others. Dr Blokhina has served as a founder and the Programme Chair of the first edition of IEEE Next Generation of Circuits and Systems Conference (NGCAS) 2017 and of IEEE ICECS 2018. In 2016-2017 Dr Blokhina was an Associate Editor for IEEE Transactions on Circuits and Systems I, and since 2018 she is the Deputy Editor in Chief of that Journal. Her research interests include the analysis, design, modelling and simulations of circuits, systems and interfaces with physical sub-systems with a particular focus on emerging applications. She has led or participated a number of projects in the area of MEMS, NEMS and micro-scale energy harvesting, distributed frequency synthesis, time series prediction on chip and interfaces with quantum devices.