Quantum Optimal Control

Accurate control over quantum systems at the level of single and multiple qubits is on top of the obvious requirement of long coherence essential for realizing advanced quantum systems and eventually practical quantum computers.
Team
Stefan Filipp, Gerhard Huber, Leon Koch, Federico Roy, Malay Singh, Ivan Tsitsilin, Max Werninghaus, Niklas Glaser
Recent publications
Quantum optimal control in quantum technologies. Strategic report on current status, visions and goals for research in Europe
Christiane P. Koch, Ugo Boscain, Tommaso Calarco, Gunther Dirr, Stefan Filipp, Steffen J. Glaser, Ronnie Kosloff, Simone Montangero, Thomas Schulte-Herbrüggen, Dominique Sugny, Frank K. Wilhelm
Research Article | EPJ Quantum Technology 9, 19  (2022)
High-speed calibration and characterization of superconducting quantum processors without qubit reset
Max Werninghaus and Daniel Egger and Stefan Filipp
Research Article | Physical Review X Quantum 2, 020324  (2021)
Preprint: arXiv:2010.06576
Leakage reduction in fast superconducting qubit gates via optimal control
Max Werninghaus and Daniel J Egger and Federico Roy and Shai Machnes and Frank K Wilhelm and Stefan Filipp
Research Article | npj Quantum Information 7, 14  (2021)
Preprint: arXiv:2003.05952

The primary focus of this line of research is on the design, optimal characterization and control of multi-qubit superconducting devices in a circuit QED architecture. We use closed-loop measurements to optimize the tune-up of the system and to obtain high-fidelity quantum gates. Moreover, we address the question how to tailor control and measurements of a complex multi-qubit quantum processor in order to obtain targeted information in the most efficient and robust way. We study experimental techniques to optimize gate operations at the pulse level. Combining these with advanced calibration and characterization methods will allow us to prepare quantum states and run algorithms with high fidelity.