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arXiv · 1311.0943

Generation of picosecond pulsed coherent state superpositions

Ruifang Dong·Anders Tipsmark·Amine Laghaout·Leonid A. Krivitsky·Miroslav Ježek·Ulrik L. Andersen
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Abstract

We present the generation of approximated coherent state superpositions - referred to as Schr\"odinger cat states - by the process of subtracting single photons from picosecond pulsed squeezed states of light at 830 nm. The squeezed vacuum states are produced by spontaneous parametric down-conversion (SPDC) in a periodically poled KTiOPO4 crystal while the single photons are probabilistically subtracted using a beamsplitter and a single photon detector. The resulting states are fully characterized with time-resolved homodyne quantum state tomography. Varying the pump power of the SPDC, we generated different states which exhibit non-Gaussian behavior.

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Ruifang Dong, Anders Tipsmark, Amine Laghaout, Leonid A. Krivitsky, Miroslav Ježek, Ulrik L. Andersen. 2013-11-05. Generation of picosecond pulsed coherent state superpositions. https://doi.org/10.1364/josab.31.001192

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