Tepetortation and entanglement sudden death in continuous variables systems

• Grant number: 09/15341-2
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): December 01, 2009
• Effective date (End): July 31, 2010
• Field of knowledge: Physical Sciences and Mathematics - Physics
• Principal Investigator: Marcelo Martinelli
• Grantee: Alencar José de Faria
• Home Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Together with the recent demonstration of the tripartite entanglement among the fields produced by an Optical Parametric Oscillator in above threshold operation, we observed an effect similar to the entanglement sudden death observed with discrete variables. This effect implies in having a system, initialy entangled, that due to the interaction with the enviromement (like losses) gets into a separable state for a finite interaction time. For continuous variable systems (like the OPO) this effect was recently observed and deserves a better study, since it is a possible limiting effect for the capacity of quantum information processing. Moreover, using the multi color entanglement of the beams provided by the OPO, we wish to perform the first teleportation of quantum information among different color of the electromagnetic spectra, providing the information transfer among separate systems operating at different frequencies.