OLAQUi: Optical Lattices and Quantum Information
Specific Targeted Research Project Contract No 013501
A system of neutral atoms stored in an optical lattice is a promising candidate for implementing scalable quantum computing.
A quantum phase transition can be used to prepare exactly one atom per lattice site, where each atom can be considered as quantum bit. Based on the socalled MottInsulator state several schemes for quantum computation have been proposed, including proposals for the creation of entanglement, computation with cluster states and quantum simulations.
It is planned to use a Mott insulator as a quantum register, in which one can encode qubits in the single atoms on each lattice site and quantum gates can be implemented acting on different atoms of the lattice.
Crucial advantages are: the simple quantumlevel structures of atoms; the insulation from the environment which leads to a strong suppression of decoherence, and the ability to trap and act on a very large ensemble of identical atoms.
An impressive example of the flexibility is the use of the internal degrees of freedom of the neutral atoms in order to generate the quantum entanglement essential of many quantum information protocols. To generate entanglement, one requires an experimental system that can be prepared in a pure atomic state, with significant and coherently controlled interactions between the particles composing the pure state.
BoseEinstein condensates fulfil these requirements.
The goal is to make quantum processing viable by using neutral atoms trapped in optical lattices.
We will focus on different challenges: preparation and initialisation of a quantum register; addressing, manipulating and measuring on single sites; twobit gates and compatible stable qubits; generation and characterisation of multiparticle entanglement states; strategies for minimising decoherence; quantum simulator; new theoretical strategies for quantum computers with optical lattices.
The final objectives of the project will provide a persistent and longterm commitment to emerging applications.


