QUROPE Quantum Information Processing and Communication in Europe

We present a unified framework to describe lattice gauge theories by means of tensor networks: this framework is efficient as it exploits the high amount of local symmetry content native of these systems describing only the gauge invariant subspace.

We demonstrate a two-pulse Ramsey-type interferometer for non-classical motional states of a Bose-Einstein condensate in an anharmonic trap. The control pulses used to manipulate the condensate wavefunction are obtained from Optimal Control Theory and directly optimised to maximise the interferometric contrast.

We study the properties of a quantum particle interacting with a one dimensional structure of equidistant scattering centres. We derive an analytical expression for the dispersion relation and for the Bloch functions in the presence of both even and odd scattering waves within the pseudopotential approximation.

Atom chips provide compact and robust platforms towards practical quantum technologies. A quick and faithful preparation of arbitrary input states for these systems is crucial but represents a very challenging experimental task. This is especially difficult when the dynamical evolution is noisy and unavoidable setup imperfections have to be considered.

Entangled atomic states, such as spin squeezed states, represent a promising resource for a new generation of quantum sensors and atomic clocks. We demonstrate that optimal control techniques can be used to substantially enhance the degree of spin squeezing in strongly interacting many-body systems, even in the presence of noise and imperfections.

We would like to draw your attention to the upcoming workshop on "New trends in complex quantum system dynamics 2015" to be held in Cartagena, Spain on 25-29 May 2015.

The workshop homepage is: http://www.cqs.upct.es

The list of invited speakers includes (confirmed):

The organizers of the "Benasque Workshop on Quantum Simulations" are pleased to announce the 4th edition of our workshop, to take place in Benasque, Spain, from February 22nd until February 27th, 2015. You can find detailed information on our website: http://www.benasque.org/2015qs/ There, you find all information to apply for contributed talk, poster presentation, or just attendance. Partial financial support is available, with students and postdocs given priority. Any additional information can be obtained by writing to info [at] benasque [dot] org.

In the recent decade, it has been discovered that QKD systems are extremely vulnerable to side-channel attacks. In particular, by exploiting the internal working knowledge of practical detectors, it is possible to bring them to an operating region whereby only certain target detectors are sensitive to detections. Crucially, the adversary can use this loophole to learn everything about the secret key without introducing any error to the quantum channel.