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[28-Apr] Experimental characterization and measurement of propagating microwave photons in superconducting circuits

posted Oct 14, 2014, 4:46 AM by Juan Jose Garcia-Ripoll   [ updated Oct 14, 2014, 4:47 AM ]
Dr. Edwin Menzel,Walther Meissner Institut, in Munich

Dual-Path State Reconstruction Scheme for Propagating Quantum Microwaves and Detector Noise Tomography, Phys. Rev. Lett. 105, 100401
Quantum state reconstruction of weak propagating microwaves to date requires the use of linear amplifiers. We introduce a theory which, even in the presence of significant amplifier noise, allows one to use these devices for measuring all quadrature moments of propagating quantum microwaves based on cross correlations from a dual-path amplification setup. Simultaneously, the detector noise properties are determined, allowing for tomography. We demonstrate the feasibility of our novel concept by proof-of-principle experiments with classical mixtures of weak coherent microwaves.

Path Entanglement of Continuous-Variable Quantum Microwaves
Phys. Rev. Lett. 109, 250502
Path entanglement constitutes an essential resource in quantum information and communication protocols. Here, we demonstrate frequency-degenerate entanglement between continuous-variable quantum microwaves propagating along two spatially separated paths. We combine a squeezed and a vacuum state using a microwave beam splitter. Via correlation measurements, we detect and quantify the path entanglement contained in the beam splitter output state. Our experiments open the avenue to quantum teleportation, quantum communication, or quantum radar with continuous variables at microwave frequencies.

Lugar: Centro de Física MA Catalán, Serrano 121 (Sala de conferencias)
Día y Hora:  Hoy, 28 de Abril, 15:00