QUROPE Quantum Information Processing and Communication in Europe

Recent technological advances have spurred on the study of topological phenomena in engineered bosonic systems. Examples of such systems include cold-atoms in optical lattices, integrated photonics, exciton-polariton systems, as well as coupled mechanical structures.

There is a significant ongoing effort in realizing quantum annealing with different physical platforms. The challenge is to achieve a fully programmable quantum device featuring coherent adiabatic quantum dynamics. Here we show that combining the well-developed quantum simulation toolbox for Rydberg atoms with the recently proposed Lechner-Hauke-Zoller~(LHZ) architecture allows one to build a prototype for a coherent adiabatic quantum computer with all-to-all Ising interactions and, therefore, a novel platform for quantum annealing.

We present optimal control protocols to prepare different many-body quantum states of Rydberg atoms in optical lattices. Specifically, we show how to prepare highly ordered many-body ground states, GHZ states as well as some superposition of symmetric excitation number Fock states, that inherit the translational symmetry from the Hamiltonian, within sufficiently short excitation times minimizing detrimental decoherence effects.

We use the sensitive response to electric fields of Rydberg atoms to characterize all three vector components of the local electric field close to an atom-chip surface. We measured Stark-Zeeman maps of S and D Rydberg states using an elongated cloud of ultracold Rubidium atoms (T ~2.5 µK) trapped magnetically 100 µm from the chip surface. The spectroscopy of S states yields a calibration for the generated local electric field at the position of the atoms.

We address the technical challenges when performing quantum information experiments with ultracold Rydberg atoms in lattice geometries. We discuss the following key aspects: (i) the coherent manipulation of atomic ground states, (ii) the coherent excitation of Rydberg states, and (iii) spatial addressing of individual lattice sites.

We study the influence of Rydberg-dressed interactions in a one-dimensional (1D) Bose-Einstein condensate (BEC). We show that a 1D geometry offers several advantages over a three-dimensional geometry for observing BEC Rydberg dressing. The effects of dressing are studied by investigating collective BEC dynamics after a rapid switch-off of the Rydberg dressing interaction.

On April 28th, QuSoft (the Dutch research centre for quantum software), the Paris Centre for Quantum Computing (PCQC) and the University of Latvia signed a memorandum of understanding to jointly push the frontiers of quantum information theory and develop quantum software for the future quantum computer.

Registration for the 14th Central European Quantum Information Processing Workshop is now open.

CEQIP is traditionally focused on current challenges and paradigms of mathematical and computational aspects of emerging quantum technologies. This year's edition will take place on May 31st - June 3rd, 2017, at the Smolenice castle, Slovakia.

Invited speakers:
Antonio Acin
Caslav Brukner
Sergey N. Filippov
Otfried Gühne
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