Make Imaging Quantum (Again)

Abstract:

Spatial entanglement of photons is frequently used in quantum imaging. For example, in ghost imaging, photons that illuminate the object being imaged are detected by a detector with no spatial resolution, while their entangled partners are incident on a camera. Correlating the detector signal with the image recorded by the camera reveals the image of the object. We proposed and demonstrated a quantum imaging method [1] that takes this approach one step further: the photon illuminating the object is not detected at all. Nevertheless, quantum interference makes it possible to obtain an image of the object, revealing both its phase and transmission. Our method is based on quantum interference, more specifically on the effect of induced coherence without induced emission discovered by the group of Leonard Mandel [2].

Although the most famous sources of quantum light emit entangled photon pairs, single fluorescent emitters in biological samples are probably the most common quantum light sources. Nevertheless, their quantum optical properties are rarely exploited. I will discuss how fluorescence microscopy can benefit from measurements of quantum correlations. Such measurements allowed enhancing the resolution of classical super-resolution methods further beyond the diffraction limit, as in the case of Quantum Image Scanning Microscopy (QISM) [3].
We found that the classical analog of QISM relying on classical light correlations offers a higher signal to noise ratio at short measurement times and is less demanding experimentally. This method, termed Super-resolution optical fluctuation image scanning microscopy (SOFISM) [4], exploits fluorescent emitter blinking as its image contrast. SOFISM offers a robust path to achieve high-resolution images with a slightly modified confocal microscope, using standard fluorescent labels and reasonable acquisition times.
[1] G. B. Lemos et al., Quantum imaging with undetected photons, Nature 512, 409–412 (2014)
[2] X. Y. Zou et al., X. Y., Induced coherence and indistinguishability in optical interference, Phys. Rev. Lett. 67, 318–321 (1991)
[3] R. Tenne, et al., Super-resolution enhancement by quantum image scanning microscopy, Nat. Phot., 13, 116–122 (2019).
[4] A. Sroda, et al., SOFISM: Super-resolution optical fluctuation image scanning microscopy, SOFISM: Super-resolution optical fluctuation image scanning microscopy, Optica 7, 1308-1316 (2020).

Chairman: B Graczykowski

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