DWELL · Preparing non-classical states in a Bose Josephson junction
FP6 — Marie Curie Actions (Human Resources and Mobility)
- Duration
- 2006-12-01 → 2008-11-30
- EU contribution
- €156,497
- Participants
- 1
- Scheme
- EIF
Lines connect the coordinator with its partners.
Results in brief
Final Activity Report Summary - DWELL (Preparing non-classical states in a Bose Josephson junction)
Entanglement, a key feature of quantum mechanics, is a resource that allows the improvement of precision measurements beyond the conventional bound reachable by classical means. This is known as the standard quantum limit, already defining the accuracy of the best available sensors for various quantities such as time or position. Many of these sensors are interferometers in which the standard quantum limit can be overcome by feeding their two input ports with quantum-entangled states, in particular spin squeezed states. During the DWELL project, we demonstrated the experimental realisation of such entangled squeezed states by splitting a Bose-Einstein condensate in a few parts using a lattice potential. This is a major step towards the realization of improved sensors using the concepts of quantum metrology.
Data: CORDIS, © European Union
Project objective
We propose to experimentally study the dynamics of a Bose-Einstein condensate in an optical double well potential, thus realizing a Bose Josephson junction.We will investigate both the mean field regime, where the junction motion is similar to the motion of a classical non-rigid pendulum, and the so-called Fock regime, in which the previous semi-classical approach fails.We will probe the crossover between the two regimes by looking at the fluctuations of the atom number difference and the phase difference between the two wells constituting the junction. This work will participate to the international research effort using cold atoms in a well-controlled environment as a new tool to investigate properties of a many body system.We will especially be interested in the regime where both quantum and thermal fluctuations play a role. Controlling this system at a quantum level can allow producing many particle entangled states giving the ability to further test quantum de-coherence theory.As an application, the production of many particle entanglement can be used to increase the precision and the sensitivity of a quantum metrology device, such as an atomic clock or an atomic interferometer.
Original text from CORDIS.
Participants
- RUPRECHT-KARLS-UNIVERSITÄT HEIDELBERG · HEIDELBERGCoordinatorGermany
Links
Data: CORDIS, © European Union