Reduction of Decoherence in Quantum Information Systems Using Direct Adaptive Control of Infinite Dimensional Systems

Mark J. Balas

Mark J. Balas, Susan A. Frost

Wang Yin-zh

In quantum information theory,quantum entangled state is a class very important resource.Detecting entanglement for states is a extremely important problem.In 2001,Nielsen M A proposed a reduction criterion,then William Hall proposed a different reduction criterion for multipartite finite dimensional systems in 2005.In this paper,we generalized above two reduction criteria to infinite dimensional multipartite quantum systems.Two class reduction criteria axe obtained for states in infinite dimensional multipartite quantum systems.

Hendra I. Nurdin, Naoki Yamamoto

Andreas Ketterer, Stephen Patrick Walborn, Arne Keller +2 more

We introduce a novel strategy, based on the use of modular variables, to encode and deterministically process quantum information using states described by continuous variables. Our formalism leads to a general recipe to adapt existing quantum information protocols, originally formulated for finite dimensional quantum systems, to infinite dimensional systems described by continuous variables. This is achieved by using non unitary and non-gaussian operators, obtained from the superposition of gaussian gates, together with adaptative manipulations in qubit systems defined in infinite dimensional Hilbert spaces. We describe in details the realization of single and two qubit gates and briefly discuss their implementation in a quantum optical set-up.

Narayan Ganesan