Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS


CATINFO Sintesi della relazione

Project ID: 501262
Finanziato nell'ambito di: FP6-MOBILITY
Paese: France

Final Activity Report Summary - CATINFO (Non-local mesoscopic cat states and quantum information)

Our project focused on building a completely new experiment using two microwave cavities. The use of two separate cavities will make it possible to manipulate field and atomic coherences over large distances (15 cm).

A major achievement was the development and test of new superconducting cavities with long photon lifetimes in a geometry which allows us to maintain the atomic coherences during the passage through the apparatus. Using mirrors consisting of superpolished copper substrates coated with a thin layer of superconducting Nb, we obtained photon lifetimes of 100 ms - an improvement of two orders of magnitude with respect to the existing ones. The lifetimes were the longest ever seen in an open resonator worldwide and were far beyond our expectations.

A lot of efforts were devoted to the planning, construction and assembly of the new setup. Many technical difficulties had to be overcome since the experiment has to be operated under vacuum at cryogenic temperatures, with very good shielding of magnetic stray fields. In order to match the cavity resonance to the atomic transition, the mechanical parts had to be manufactured and carefully put together with micrometer precision. Moreover, a computer control system had to be developed in order to realise complex experimental sequences and to simplify and to accelerate the data acquisition.

Now, the setup is almost finished and has reached a state where very interesting experiments such as atomic state quantum teleportation or the realisation of non-local mesoscopic field states can be envisaged in the near future. Especially the photon lifetimes of 100 ms will allow fascinating experiments such as quantum non-demolition measurements to monitor the evolution of a many-photon quantum states in the cavity.


Tel.: 331 42 34 94 51
Fax: 331 43 26 87 23