Quantum phenomena along holography open a myriad of new perks in the sensing field. Our work succeeds to built holograms using nonclassical light states to overcome current detection limitations for wavelengths out of visible spectra.
Holography exploits the interference of a light field reflected/transmitted from an object with a reference beam to obtain a reconstruction of the spatial shape of the object. Classical holography techniques have been very successful in diverse areas such as microscopy, manufacturing technology, and basic science. However, detection constraints for wavelengths outside the visible range restrict the applications for imaging and sensing in general. For overcoming these detection limitations, we implement phase-shifting holography with nonclassical states of light, where we exploit quantum interference between two-photon probability amplitudes in a nonlinear interferometer. We demonstrate that it allows retrieving the spatial shape (amplitude and phase) of the photons transmitted/reflected from the object and thus obtaining an image of the object despite those photons are never detected. Moreover, there is no need to use a well-characterized reference beam, since the two-photon scheme already makes use of one of the photons as reference for holography.
This work presents synthetic off-axis quantum holography with undetected light, a novel approach to obtain holographic information with a single acquisition. Holography is a vital tool for imaging [1] but is mainly limited to the visible range caused by the availability of efficient detectors. Interesting applications, like identifying molecular signatures and analyzing material properties are excluded, particularly those requiring detection in regions outside the visible spectra of light, for example the mid-infrared [2]. Quantum holography with undetected light (QHUL) was presented in 2022 [3] to give access to these harder-to-detect wavelength regions. However, it is required to do multiple acquisitions to reconstruct the amplitude and phase, preventing the usage in dynamic processes.