Experimental realization of non-Abelian non-adiabatic geometric gates
Friday, 07 Jun. 2013, 15:30 - 16:30
Presenter: Stefan FILIPP - ETH Zürich
Where: Atominstitut Hörsaal, Stadionallee 2, 1020 Wien
The evolution of a quantum system can result in a geometric phase which depends - in contrast to the dynamic phase - only on the path of the system's state in Hilbert space. As a consequence, only fluctuations which distort the path contribute to geometric dephasing, if the system is subjected to noise. This noise-resilience of the geometric phase holds promise for robust quantum computation. In our experiments, we study geometric phases with superconducting artificial atoms (transmons) in the circuit quantum electrodynamics architecture. By adding artificial perturbations to the drive parameters, we have first verified the robustness of geometric phases with respect to noise that leaves the path unaffected . We have then realized geometric single-qubit gates which are based on matrix-valued generalizations of geometric phases to degenerate quantum systems, so-called non-Abelian holonomies, and verified their non-commuting character . When assisted by two-qubit gates, these operations may form the basis for a universal set of geometric quantum gates.
 S. Berger, M. Pechal, A.A. Abdumalikov, C. Eichler, L. Steffen, A. Fedorov, A. Wallraff, and S. Filipp. arXiv:1302.3305 (2013)
 A.A. Abdumalikov, J. M. Fink, K. Juliusson, M. Pechal, S. Berger, A. Wallraff, and S. Filipp. Nature 496, 482 (2013).