ESPCI web site
Thursday, December 17 2PM (Paris time)
Generating two continuous entangled microwave beams using a dc-biased
Josephson junction
Entanglement is one of the most striking prediction of quantum mechanics
that has no equivalent in classical experience we have of the world.
When two superconducting leads are separated by a thin insulating barrier
under a dc bias, the transport of electrical charges can only occur when
electrons, paired as Cooper pairs, dissipate their energy into photonic
excitation of the junction’s environment. By properly designing two
microwave resonators at two different frequencies coupled to the Josephson
junction we can extract the statistic of the emission and study the
properties of the emitted light. I will show, through an entanglement
witness, that photonic fluxes generated by a Cooper pair current are
actually entangled between each other, even though they are separated both
in frequencies and in space. I will also discuss the decoherence processes
that take place leading to a degradation of the quality of the entanglement
of the photon flux with time.
[1] A. Peugeot, G. Ménard et al. Generating two continuous entangled
microwave beams using a dc-biased Josephson junction, arxiv:2010.03376
(2020).
