Ghost imaging with multipartite entangled quantum light states

Andrew Forbes

Milena D’Angelo, Alejandra Valencia, Morton H. Rubin +1 more

The quantum ghost imaging phenomena, experimentally demonstrated a decade ago, exploited the apparent spooky action at a distance of entangled photon pairs and offered a novel approach toward imaging. Can ghost imaging effects be produced by ``classical'' light sources, such as separable systems of photon pairs or thermal light? If so, can these sources achieve the same accuracy achieved by entangled states? In order to answer these questions, we formulate the different physics behind entangled and separable systems in terms of a set of inequalities derived from the historical argument of Einstein, Podolsky, and Rosen. We show that the ghost images produced by separable sources are subject to the standard statistical limitations. However, entangled states offer the possibility of overcoming such limitations. Imaging can, therefore, achieve its fundamental limit through the high spatial resolution and nonlocal behavior of entangled systems.

Xiaolong Dong, Dongyu Liu, Mingsheng Tian +6 more

Ghost imaging can be implemented with illumination light with pronounced quantum characters. In this work, we address the inverse problem of ghost imaging, i.e., the tomography of the quantum states of illumination light based on ghost imaging. We showcase the characterization of multimode Gaussian state light represented by its covariance matrix. With the information of spatial modes, we reconstruct the quantum states of light using the variation of SNR of the ghost images formed by the input light under a given set of optical operations. We demonstrate that ghost imaging can also be used to characterize the non-Gaussian light by its deviation from Gaussian states, which can serve as a criterion for the non-Gaussianity of the input light. The spatial resolving power of the proposed method can be advantageous for quantum information applications involving structured light, such as multiplexing with spatial modes.

Ronald E. Meyers, Keith S. Deacon

Felix Jaetae Seo, Quinton Rice, Dulitha Jayakodige +2 more

Yuto Takahashi, Tiancheng Wang, Shogo Usami +1 more

Quantum ghost imaging is the protocol that uses entanglement to obtain images of an object, which was realized by T.B. Pittman et al. In quantum ghost imaging, one of the two entangled lights is illuminated to the object, and the other is illuminated directly to the detector. Then, the image of the object is generated by correlating the intensity of these lights. Thus, compared to ordinary cameras, it is less affected by noise. However, it takes a long time to obtain the image of the object because it requires many times of illuminations of light. Therefore, in this study, we consider quantum ghost imaging that illuminates multiple positions simultaneously. We evaluate the effect of reducing the time to obtain the image by multiple positions illumination by the peak signal-to-noise ratio performance of quantum ghost imaging depending on the number of illuminated positions N and transmissivity η. Then we clarify that large N realizes better performance than small N when the attenuation is severe but a value of N that is too large degrades the performance when the attenuation is low.