Towards the teleportation between rubidium atoms and light in the telecom C-band

• Autor(a) principal: Pinto Filho, Luiz Couto Corrêa
• Data de Publicação: 2020
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: https://www.teses.usp.br/teses/disponiveis/43/43134/tde-24112020-115051/
• topic: Atomic Polarization.; Emaranhamento; Entanglement; Optical Parametric Oscillator; Oscilador Paramétrico Óptico; Polarização Atômica.; Teleportation; Teletransporte

We developed a system capable of generating bipartite entanglement, and with promising results towards the generation of tripartite entangled states of light, using an Optical Parametric Oscillator. The generated fields are resonant with the Rubidium D2 transition line at 780 nm for the reflected pump, and with the C-band of telecommunications channels at 1560 nm for signal and idler. We verified that phonon noise in the crystal was responsible for introducing phase noise and that lowering the temperature of the system would reduce the noise, improving the prospects of obtaining tripartite entanglement. In a separate experiment, we built an optical pumping system in which, along with a magnetic shield and magnetic fields generated by coils, we were able to prepare and characterize an atomic polarization state with an orientation p=0.9 and a polarization noise of 2.6 dB above the shot noise limit at a central frequency of 23.5 kHz and a linewidth of 70 Hz. These two systems were built as the first steps towards the implementation of a teleportation protocol between atoms and light resonant at different wavelengths, setting the foundations for the implementation a quantum network.