2007 APS March Meeting
Volume 52, Number 1
Monday–Friday, March 5–9, 2007;
Denver, Colorado
Session N2: Progress in Superconducting Quantum Computing
8:00 AM–11:00 AM,
Wednesday, March 7, 2007
Colorado Convention Center
Room: Four Seasons 4
Sponsoring
Units:
GQI DCMP
Chair: Robert Schoelkopf, Yale University
Abstract ID: BAPS.2007.MAR.N2.1
Abstract: N2.00001 : Superconducting qubits on the way to a quantum processor*
8:00 AM–8:36 AM
Preview Abstract
Abstract
Author:
Frank Wilhelm
(IQC and Physics Department, University of Waterloo, 200 University Ave W, Waterloo, ON, N2L 3G1, Canada)
Experimental research on supeconducting qubits has seen an
enormous progress in recent years. About 10 years after its first
theoretical proposals, experiments have demonstrated the
necessary building blocks for the exploration of quantum
information along several avenues: Single qubit-rotations, long
coherence times, high-fidelity nondemolition readout, two-qubit
interactions and gates, coupling to delocalized qubit modes. With
this progress, analogies to other qubit candidates such as
magnetic resonance systems, atomic, and optical systems are
evident, but we also see the specific strengths of
superconducting qubits play out - in situ tunable strong
qubit-qubit coupling, strong coupling between qubits and the
quantized electromagnetic field, strong intrinsic nonlinearity,
and the possibility to fabricate large circuits. Most of these
achievements will be discussed later in the session.
I will give an introduction to superconducting qubits in the
perspective of quantum information processing [1] accessible to
outsiders in the field. I will put the different elements of the
session in the perspective of an actual scalable architecture
which allows for fault-tolerant quantum computation [1,2]. In
order to make further progress in direction, the fidelities of
quantum operations need to be improved. I will discuss the
crucial topic of understanding and further supressing noise from
material defects in these systems, which can influence both the
phase and bit-flip error rate [3,4]. I will show, how optimal
control theory can help to find fast and high-fidelity shaped
pulses for superconducting qubits, even though they, other than
spin 1/2 systems, have relatively close leakage levels outside the
qubit manyfold [5,6]. This technique also allows to optimize
pulses in the presence of telegraph noise [6]. Finally, I will
describe how the strong nonlinearity of Josephson circuit can be
used for the generation of single microwave photons [7] and lead
to a nonlinear generalization of cavity quantum electrodynamics
effects [8].\newline
\newline
[1] M.R. Geller, E.J. Pritchett, A.T. Sornborger, and F.K.
Wilhelm quant-ph/0603224 \newline
[2] A.G. Fowler, W. Thompson, Z. Yan, A.H. Majedi, and F.K.
Wilhelm, in preparation\newline
[3] R. de Sousa, K.B. Whaley, F.K. Wilhelm, and J. von Delft,
Phys. Rev. Lett 95, 247006 (2005)\newline
[5] A.K. Sporl, T. Schulte-Herbrueggen, S.J. Glaser, V. Bergholm,
M.J. Storcz, J. Ferber, and F.K. Wilhelm
quant-ph/0504202\newline
[6] P. Rebentrost, I. Serban, T. Schulte-Herbrueggen, and F.K.
Wilhelm, in preparation\newline
[7] M. Mariantoni, M.J. Storcz, F.K. Wilhelm, W.D. Oliver, A.
Emmert, A. Marx, R. Gross, H. Christ, and E.
Solano, cond-mat/0509737\newline
[8] I. Serban, E. Solano, F.K. Wilhelm, cond-mat/0606734.
*Work supported in parts by the DFG through SFB 631, the EU through EuroSQIP, NSERC Discovery Grants, and the University of Waterloo
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.MAR.N2.1