Observation of 65 GHz Coherent Oscillation in a Superconducting Flux Qubit Manipulated by Pulses

11th European Conference on Applied Superconductivity

Chiarello, F.^1 ; Carelli, P.^2 ; Castellano, M.G.^1 ; Cosmelli, C.^3 ; Torrioli, G.^1

IFN-CNR, via Cineto Romano 42, Rome

00156, Italy^1

DSFC, Universitá dell'Aquila, via Vetoio 1, L'Aquila

67100, Italy^2

Dep. Physics, Sapienza Universitá di Roma, P.le A. Moro 5, Rome

00185, Italy^3

关键词: Coherent oscillations;    Harmonic potential;    Initial conditions;    Landau-zener transitions;    Quantum interference;    Quantum operations;    Superconducting flux;    Superconducting qubits;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/507/4/042006/pdf
DOI  :  10.1088/1742-6596/507/4/042006

来源: IOP

【 摘 要 】

A superconducting flux qubit can be manipulated by a fast modification of its potential, with a rapid transition from a double well to a single well shape, and coming back to the initial condition. This mechanism is based on a non-trivial quantum phenomenon, involving «partial» Landau-Zener transitions, coherent evolution in an harmonic potential and quantum interference. The study of this system enables a deep insight in decoherence mechanisms typical of superconducting qubits. Moreover, this procedure allows quantum operations with extreme high speeds, not possible with other standard manipulations. We present the experimental observation of coherent oscillations showing tunable frequencies with a 65 GHz top value.