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Quantum dynamics of an electromagnetic mode that cannot contain N photons

April 26, 2016 - 11:00am
Dr. Landry Bretheau

L. Bretheau1,2, P. Campagne-Ibarcq1, E. Flurin1, F. Mallet1, B. Huard1
1 Laboratoire Pierre Aigrain, Ecole Normale Supérieure-PSL Research University, CNRS, Université Pierre et Marie Curie–Sorbonne Universités, Université Paris Diderot–Sorbonne Paris Cité, 24 Rue Lhomond, 75231 Paris, France

2 Present address: Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States

Electromagnetic modes are instrumental in building quantum machines. In this experiment [1], performed in a
circuit Quantum Electrodynamics architecture, we introduce a method to manipulate these modes by effectively controlling their phase space. Preventing access to a single energy level, corresponding to a number of photons N, confined the dynamics of the field to levels 0 to N-1. Under a resonant drive, the level occupation was found to oscillate in time, similarly to a spin N/2. Performing a direct Wigner tomography of the field revealed its nonclassical features, including a Schrödinger cat-like state at half period in the evolution. This fine control of the field in its phase space may enable applications in quantum information and metrology.

[1] L. Bretheau, P. Campagne-Ibarcq, E. Flurin, F. Mallet, B. Huard, Science, 348, 776-779 (2015).
PSC 2136
College Park, MD 20742

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