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arXiv · 1706.07018

Measurement-induced strong Kerr nonlinearity for weak quantum states of light

Luca S. Costanzo·Antonio S. Coelho·Nicola Biagi·Jaromír Fiurášek·Marco Bellini·Alessandro Zavatta
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Abstract

Strong nonlinearity at the single photon level represents a crucial enabling tool for optical quantum technologies. Here we report on experimental implementation of a strong Kerr nonlinearity by measurement-induced quantum operations on weak quantum states of light. Our scheme coherently combines two sequences of single photon addition and subtraction to induce a nonlinear phase shift at the single photon level. We probe the induced nonlinearity with weak coherent states and characterize the output non-Gaussian states with quantum state tomography. The strong nonlinearity is clearly witnessed as a change of sign of specific off-diagonal density matrix elements in Fock basis.

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Luca S. Costanzo, Antonio S. Coelho, Nicola Biagi, Jaromír Fiurášek, Marco Bellini, Alessandro Zavatta. 2017-06-21. Measurement-induced strong Kerr nonlinearity for weak quantum states of light. https://doi.org/10.1103/physrevlett.119.013601

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