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Frontiers in Optics

Long-Pass Type Quantum Imaging Interferometer with Undetected Photons in the Infrared Wavelength Range

Bernd Jungbluth, Florian Elsen, Florian Herbst, Hans-Dieter Hoffmann

Published Jan 1, 2020• 0 citations
Publisher

Abstract

We present a parametric down conversion source in periodically poled lithium niobate, its application in a quantum interferometer at 1600 nm and a novel long-pass scheme to extend the operational range further into Mid-IR.
DOI
10.1364/fio.2020.jth4a.38

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Quantum sensing in the infrared regime often demands the use of expensive and cryogenically operated detectors. Nonlinear interferometry has paved the way for information transfer from the infrared to the near--infrared or visible regime in various quantum technologies. A particularly interesting application of these interferometers involves spectrally--resolved quantum imaging using undetected photons, enabled by the use of temperature--tunable parametric amplifiers. In this work, we demonstrate spectrally resolved transmission imaging with undetected photons around 1550 nm using a spontaneous parametric down conversion based folded nonlinear interferometric scheme, registering the attenuation of a zebrafish larva as a biological feasibility test. We characterize and calibrate the interferometer, having achieved spectrally resolved interference fringes with a maximum baseline visibility of ∼74%\sim 74\%∼74% in the near--infrared regime. Phase--stepped readout of a grating spectrometer gives a resolving power of ∼1460\sim1460∼1460 (from the spectrometer's point spread function) at 1550 nm, and ∼730\sim 730∼730 from the coherence length, the finest reported for imaging with undetected photons, over an instantaneous spectral window of ≈51\approx 51≈51 cm−1^{-1}−1.
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