Quantum systems engineering

Abstract:

An appropriate semiclassical limit for a general cubic nonlinear Schrodinger equation, or Gross-Pitaevskii equation was derived. The derivation was shown to be a Liouville-type equation. Using this derivation, it was demonstrated how an eccentric wave function φ (x) can produce large deviations from the semiclassical limit.

Abstract:

We review recent proposals for performing entanglement manipulation via cold collisions between neutral atoms. State-dependent, time-varying trapping potentials allow one to control the interaction between atoms, so that conditional phase shifts realizing a universal quantum gate can be obtained with high fidelity. We discuss possible physical implementations with existing experimental techniques, for example optical lattices and magnetic micro-traps. © 2000 Taylor & Francis Group, LLC.

Abstract:

Quantum optical systems that implement quantum computing tasks concentrating on two-qubit gates are presented. Two schemes, one based on dipole moments of Rydberg atoms and the other base on conditional Coulomb interactions between ions in arrays of micro-traps, are analyzed. These schemes are combined with the features of quantum optics, in particular quantum control and long decoherence times.

Abstract:

We review recent proposals for performing entanglement manipulation via controlled interactions between trapped atoms. State-dependent, time-varying microscopic potentials allow one to obtain with high fidelity a conditional phase shift realizing a universal quantum gate. We discuss possible physical implementations with existing experimental techniques, for example optical lattices and magnetic micro-traps.

Abstract:

We develop a method to entangle neutral atoms using cold controlled collisions. We analyse this method in two particular set-ups: optical lattices and magnetic microtraps. Both offer the possibility of performing certain multi-particle operations in parallel. Using this fact, we show how to implement efficient quantum error correction and schemes for fault-tolerant computing. © 2000 Taylor & Francis Group, LLC.