Nonlinear Optics With Less Than One Photon
A poster presented at The Physics Of Quantum Electronics 2001 in Snowbird, Utah

K. J. Resch, J. S. Lundeen, and A. M. Steinberg (presented by Lundeen)
Department of Physics, University of Toronto

We present an experiment in which spontaneous parametric down-conversion is suppressed or enhanced by interference with two photons from a classical local-oscillator field. When there is destructive interference, any photon pairs from the laser field undergo sum-frequency generation and are removed from the beam. In this sense, there is an effective two-photon nonlinearity which is significant even when only two photons are present at a time; the nonlinearity is observable at the quantum level because it is enhanced through the mediation of the strong classical field, which acts as a spectator. Although the scheme is accompanied by inevitable quantum noise, it functions essentially as an absorptive two-photon optical switch.

Introduction and Background

Interference with Downconverted Photons: The Switch

Experimental Setup

Experimental Results and Summary:

A PDF version of the entire poster

This page is maintained by Jeff Lundeen.
Last updated Feb 10th, 2001

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