The Project is aimed at the implementation of the Active Quantum State Teleportation and at the realization of a source of multiparticle entangled states in quantum superposition by Quantum Injected Optical Parametric Amplification.
These objectives require the study of new methods for the creation, detection, amplification of multiparticle entangled states with large quantum efficiencies (QE):
1) A high QE generator of entangled pairs by Spontaneous Parametric Down Conversion with investigation and implementation of the field's singularities of the coupled beams;
2) A new high QE radiation trapping linear detector. These devices will be used for the realization of relevant protocols in the fields of quantum information, such as:
a) Implementation of Quantum Error Correction within Active Quantum State Teleportation;
b) Realization of a Universal Optimum Quantum Cloning Machine.
DESCRIPTION OF WORK
The Active Teleportation will be implemented by employing:
A) a novel high QE optical generator of entangled photons;
B) a fast Electro Optic (EO) scheme for fast swithching;
C) a high QE photomultiplier detection system triggering the EO system. The high QE generator of photon couples is based on multiple interaction of a high intensity UV femtosecond laser beam with a single Type I nonlinear crystal. It allows the generation of all four Bell-type characters of entanglement for photon couples with an expected large QE. The optimisation of this device requires investigation on several aspects of the interaction NL dynamics e.g. the study of the role of the spatial field's singularities in non-linear parametric down-conversion. The QE of the detection apparatus will be also improved (up to a value >90%) by a novel radiation-trapping method applied to fast linear detectors, i.e. capable of counting the number of particles detected simultaneously. By adoption of the above results, a quantum-injected optical parametric amplifier will be developed.
It will be used for three purposes:
a) to perform unitary squeezing transformations of the single photon state with generation of all optical multiphoton quantum superposition, or Schroedinger-Cat states;
b) to implement a universal optimum quantum cloning machine;
c) to implement the three-qubit Quantum Error Correction and Purification protocol for quantum computation;
d) To undertake, by the new methods above, new investigations in the domain of modern quantum measurement physics, e.g. by new joint POVM Positive operator valued measurements of non commuting observables;
e) to undertake nonlocality test of violation of Bell inequalities in the multiparticle regime. The Program will require the joint effort of five scientific Laboratories in Europe and Israel.
Funding SchemeCSC - Cost-sharing contracts
2300 RA Leiden
BS8 1TH Bristol