Distinguishability and the Physics of Quantum Information
The aim of the research project proposed herein lies in the application of recent quantum-information approaches concerning the characterisation of wave-particle Duality in two-way interferometers, in order to design new devices for the quantum processing of information.
We consider a pair of two-way interferometers coupled by a dispersive interaction at their central stage. At the point of maximum entanglement, the fringe visibility of both interferometers are totally degraded, demonstrating quantum-information-based wave-particle Duality. We have also shown in a preliminary theoretical calculation that the perfect correlations established at this point enables Bell-state engineering and, in addition, can be used for the design of a quantum controlled-NOT gate. We plan to develop a full characterisation of this multi task device, according to quantum Information Theory. Special attention has to be paid to practical implementation factors, such as decoherence, which could limit the performance of this device. The goals of the project can be linked with the aims of the European Research Network The Physics of Quantum Information.