2. QUANTUM INFORMATION FOR MANY PARTICLE AND CONDESED MATTER SYSTEMS

Entanglement is a resource of quantum information theory that can be used for communicational and computational tasks. Entanglement has been so far mainly studied for small numbers of qubits as multi-qubit entanglement is either hard to study theoretically or it is too fragile to create in the laboratory. It is intriguing that typical manipulations in optical lattices exhibit novel features in terms of quantum information processing that appear in large collection of qubits up to the order of hundreds of thousands. It is valuable to study the entanglement properties in these systems and derive criteria for their qualitative and quantitative study and optimisation.
An important part of my research lies within the area of topological objects like anyons, Skyrmions or others obtained as collective phenomena in condensed matter physics. I study such phenomena within the optical lattice setup where fractional statistics or phase transitions can be well simulated actually providing the analogue quantum computer (well controlled physical systems) for simulating hard problems in the arena of topological effects.

References:
[1] J. K. Pachos (2004), Quantum phases of electric dipole ensembles in atom chips, cond-mat/0405374.
[2] J. K. Pachos and E. Rico (2004), Effective three-body interactions in triangular optical lattices, Phys. Rev. A 70, 053620, quant-ph/0404048.
[3] A. Kay et al. (2004), Quantum information and triangular optical lattices, quant-ph/0407121.