QUROPE Quantum Information Processing and Communication in Europe

IThe SOLID group of Lieven Vandersypen recently published a paper in Physical Review Letters in which they investigated phonon-induced spin and charge relaxation mediated by spin-orbit and hyperfine interactions for a single electron confined within a double quantum dot. They extract an electron spin relaxation rate that varies nonmonotonically with the detuning between the dots and confirm this model with experiments performed on a GaAs double dot.

The Quantronics group at SOLID partner CEA have recently published a paper in Physical Review Letters in wihch they measure the quantum fluctuations of a pumped nonlinear resonator using a superconducting artificial atom as an in situ probe. The qubit excitation spectrum provided access to the frequency and amount of excitation of the intracavity field fluctuations, from which we infer its effective temperature.

The Chalmers team led by Chris Wilson recently published a paper in Physical Review Letters in which they investigated the effective interaction between two microwave fields, mediated by a transmon-type superconducting artificial atom that is strongly coupled to a coplanar transmission line. The interaction between the fields and atom produces an effective cross–Kerr coupling.

We study the nonequilibrium dynamics of correlations in quantum lattice models in the presence of long-range interactions decaying asymptotically as a power law. For exponents larger than the lattice dimensionality, a Lieb-Robinson-type bound effectively restricts the spreading of correlations to a causal region, but allows supersonic propagation. We show that this decay is not only sufficient but also necessary.

• Quantum information processing: Entanglement theory, correlation measures,
• Foundations of quantum mechanics: Quantum contextuality, Bell inequalities

The Workshop on Quantum Telecommunications will be held on 15-17 May 2013, in Lisbon, and aims at disseminating the latest theoretical and experimental results in quantum telecommunications, quantum information and quantum cryptography, in an informal setting, with plenty of time for discussions. The number of participants is limited.

For more information and registration, please see:
http://www.qtworkshop.org/

We theoretically investigate the properties of a double-well bosonic Josephson junction coupled to a single trapped ion.