QUANTUM OPTICS WITH PROPAGATING MICROWAVE PHOTONS
Andreas Wallraff (ETH Zurich, Switzerland)

Infos Complémentaires

13h30 - Room 236 - 2nd floor
29 rue d’Ulm, Paris
Contact : benjamin.huard@ens.fr, aleksandra.walczak@ens.fr
http://www.phys.ens.fr/

Jeudi 17 janvier 2013

Using modern micro and nano-fabrication techniques combined with superconducting
materials we realize quantum electronic circuits. We create, store, and manipulate
individual microwave photons on chip. The strong interaction of photons with
superconducting quantum two-level systems allows us to probe fundamental quantum
effects of light and also to develop components for applications in quantum
information technology.

In this presentation, I will discuss how we realize on-demand single photon sources
which we characterize using correlation function measurements and full quantum
state tomography. For this purpose we have developed efficient methods to separate
the quantum signals of interest from the noise added by the linear amplifiers
used for quadrature amplitude detection. We now regularly employ our own superconducting
parametric amplifiers to perform nearly quantum limited detection of
propagating electromagnetic fields. These enable us to probe the entanglement
which we generate on demand between stationary qubits and microwave photons
freely propagating down a transmission line. Using two independent microwave
single photon sources, we have recently performed Hong-Ou-Mandel experiments
and have probed the coherence of two-mode multi-photon states at the out-put of
the beam-splitter. The non-local nature of such states may prove to be useful for distributing
entanglement in future small-scale quantum networks.

13h30 - Room 236 - 2nd floor
29 rue d’Ulm, Paris
Contact : benjamin.huard@ens.fr, aleksandra.walczak@ens.fr
http://www.phys.ens.fr/