MINES ParisTech CAS - Centre automatique et systèmes


Séance du jeudi 19 septembre 2019, Salle L106, 14h00-15h00.

Paulo Sergio PEREIRA DA SILVA, University of Sao Paulo, Brazil

The main subject of this talk is the Reference Input Generation Algorithm - RIGA [1], a fast and powerful algorithm for constructing control pulses for state and quantum gate preparations for closed quantum systems . The first part of this talk is devoted to the presentation of this algorithm and its convergence properties. Two numerical implementations are discussed in the second part of this talk: the piecewise-constant and the smooth versions of RIGA. We shall show that the piecewise-constant implementation can be considered as a closed-loop version of GRAPE. We will present the smooth implementation, which considers a fast and precise 4th-order Runge-Kutta integration scheme in a transformed space (an open subset of u(n)). In the third part of this talk, we shall present several numerical experiments with the smooth version of RIGA, considering state preparation, and quantum gate generation. For these numerical experiments, we shall consider a N-qubit system (with N=2, 3, ... .10 qubits) and a system of two coupled transmon qubits.

[1] P. S. Pereira da Silva, H. B. Silveira, P. Rouchon,(2019), Fast and virtually exact quantum gate generation in U(n) via iterative Lyapunov methods, International,Journal of Control, doi:10.1080/00207179.2019.1626023