arXiv:1711.09171 · Optics Express

Interaction-free ghost-imaging of structured objects

Yingwen Zhang, Alicia Sit, Frédéric Bouchard, Hugo Larocque, Florence Grenapin, Eliahu Cohen, Avshalom C. Elitzur, James L. Harden, Robert W. Boyd, Ebrahim Karimi

Published Jan 24, 2019• 66 citations

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Abstract

Quantum - or classically correlated - light can be employed in various ways to improve resolution and measurement sensitivity. In an "interaction-free" measurement, a single photon can be used to reveal the presence of an object placed within one arm of an interferometer without being absorbed by it. With a technique known as "ghost-imaging", entangled photon pairs are used for detecting an opaque object with significantly improved signal-to-noise ratio while preventing over-illumination. Here, we integrate these two methods to obtain a new imaging technique which we term "interaction-free ghost-imaging" (IFGI). With this new technique, we reduce photon illumination on the object by up to 26.5% while still maintaining at least the same image quality of conventional ghost-imaging. Alternatively, IFGI can improve image signal-to-noise ratio by 18% when given the same number of interacting photons as in standard ghost-imaging. IFGI is also sensitive to phase and polarisation changes of the photons introduced by a structured object. These advantages make IFGI superior for probing light-sensitive materials and biological tissues.

DOI: 10.1364/oe.27.002212

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