Observation of very long-lived entanglement

Brian Julsgaard, Alexander Kozhekin, Eugene Simon Polzik

Hartmut Häffner, Ferdinand Schmidt‐Kaler, W. Hänsel +10 more

T. Körber, Christian F. Roos, W. Hänsel +8 more

We report on the preservation of bi-partite entanglement in an ion trap for over 10 seconds.

Cheng Yao, Wang, Zhongming

We report the resonant propagation of the long-lived Mossbauer gamma in the time-resolved Mossbauer spectroscopy. Recently, three entangled gammas emitted from the E3 rhodium Mossbauer transition has been proposed to interpret the extraordinary observations in the previous report. Further observation reported here is the dynamic beat of these entangled gammas at room temperature and 77K. Apparent beat anisotropy reveals their long-distance resonant propagation, which leads to suppressed Doppler shift of entangled photon transport in the Borrmann channel.

Francesco Riggi

Jens Lykke Sørensen, Brian Julsgaard, C. Schori +1 more

Summary form only given. The spin polarized ground state of a cesium gas in a paraffin coated glass cell at room temperature has been recently used for generation of a long lived entangled state of atoms. In this paper we report on the first results towards using this medium as a quantum memory for polarization states of a light beam. The possibility of a reversible transfer of polarization states between light and atoms via interspecies teleportation protocols has been previously proposed. A narrowband tunable source of entangled light needed for such a transfer has been constructed before. We demonstrate that our set-up allows detection of the quantum state of light propagating through an atomic sample by means of observing the state of the long lived collective spin of the sample. For this purpose a polarization squeezed optical probe is prepared by mixing orthogonally polarized squeezed vacuum and coherent light with a variable phase on a polarizing beamsplitter.