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Related papers: Quantum Imaging with Incoherent Photons

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This paper attempts a probe into negative refraction without absorption by means of an incoherent pump field and a strong coherent field coupling the dense four-level atomic system.With the application of the incoherent pump field to…

Quantum Physics · Physics 2024-03-05 Shun-Cai Zhao , Zheng-Dong Liu , Qi-Xuan Wu

Pixelation occurs in many imaging systems and limits the spatial resolution of the acquired images. This effect is notably present in quantum imaging experiments with correlated photons in which the number of pixels used to detect…

A practical source of high fidelity entangled photons is desirable for quantum information applications and exploring quantum physics. Semiconductor quantum dots have recently been shown to conveniently emit entangled light when driven…

The propagation of $N$ photons in one dimensional waveguides coupled to $M$ qubits is discussed, both in the strong and ultrastrong qubit-waveguide coupling. Special emphasis is placed on the characterisation of the nonlinear response and…

We show that the resolution "per absorbed particle" of standard absorption tomography can be outperformed by a simple interferometric setup, provided that the different levels of "gray" in the sample are not uniformly distributed. The…

Quantum Physics · Physics 2009-11-07 P. Facchi , Z. Hradil , G. Krenn , S. Pascazio , J. Rehacek

Extracting information from weak optical signals is a critical challenge across a broad range of technologies. Conventional imaging techniques, constrained to integrating over detected signals and classical post-processing, are limited in…

Quantum Physics · Physics 2025-12-18 Aleksandr Mokeev , Babak Saif , Mikhail D. Lukin , Johannes Borregaard

Over the last several decades, entangled photon pairs generated by spontaneous parametric down conversion processes in both second-order and third-order nonlinear optical materials have been intensively studied for various quantum features…

Quantum Physics · Physics 2021-02-19 B. S. Ham

Single photons provide excellent quantum information carriers, but current schemes for preparing, processing and measuring them are inefficient. For example, down-conversion provides heralded, but randomly timed single photons, while…

Quantum Physics · Physics 2012-02-07 N. K. Langford , S. Ramelow , R. Prevedel , W. J. Munro , G. J. Milburn , A. Zeilinger

Quantum illumination is an entanglement-based target detection protocol that provides quantum advantages despite the presence of entanglement-breaking noise. However, the advantage of traditional quantum illumination protocols is limited to…

Quantum Physics · Physics 2024-06-26 Xiaobin Zhao , Zheshen Zhang , Quntao Zhuang

We construct optimal measurements, achieving the ultimate precision predicted by quantum theory, for the simultaneous estimation of centroid, separation, and relative intensities of two incoherent point sources using a linear optical…

Quantum Physics · Physics 2018-07-04 J. Rehacek , Z. Hradil , D. Koutny , J. Grover , A. Krzic , L. L. Sanchez-Soto

Large scale quantum information processing requires stable and long-lived quantum memories. Here, using atom-photon entanglement, we propose an experimentally feasible scheme to realize decoherence-free quantum memory with atomic ensembles,…

Quantum Physics · Physics 2008-11-05 Feng Mei , Ya-Fei Yu , Zhi-Ming Zhang

Quantum phenomena such as entanglement can improve fundamental limits on the sensitivity of a measurement probe. In optical interferometry, a probe consisting of $N$ entangled photons provides up to a $\sqrt{N}$ enhancement in phase…

We investigate quantum interrogation techniques which allow imaging information about semi-transparent objects to be obtained with lower absorption rates than standard classical methods. We show that a gain proportional to log N can be…

Quantum Physics · Physics 2007-05-23 Adrian Kent , David Wallace

A quantum superposition of two coherent states of light with small amplitude can be obtained by subtracting a photon from a squeezed vacuum state. In experiments this preparation can be made conditioned on the detection of a photon in the…

Quantum Physics · Physics 2014-10-09 Anne E. B. Nielsen , Klaus Mølmer

While experimental measurements of photon correlations have become routine in laboratories, theoretical access to these quantities for the light generated in complex nanophotonic devices remains a major challenge. Current methods are…

Quantum illumination uses quantum correlations to enhance the detection of an object in the presence of background noise. This advantage has been shown to exist even if one uses non-optimal direct measurements on the two correlated modes.…

Quantum Physics · Physics 2023-11-06 Thomas Brougham , Nigam Samantaray , John Jeffers

In this work, a theoretical generalization of Lloyd's quantum illumination to signal beams described by two entangled photon states is developed. It is shown that the new protocol offers a method to find the range of the target, reduces the…

Quantum Physics · Physics 2021-09-21 Ricardo Gallego Torromé , Nadya Ben Bekhti-Winkel , Peter Knott

We propose a novel method for image representation in quantum computers, which uses the two-dimensional (2-D) quantum states to locate each pixel in an image through row-location and column-location vectors for identifying each pixel…

Multimedia · Computer Science 2015-07-20 Madhur Srivastava , Subhayan R. Moulick , Prasanta K. Panigrahi

The reconstruction of density matrices from measurement data (quantum state tomography) is the most comprehensive method for assessing the accuracy and performance of quantum devices. Existing methods to reconstruct two-photon density…

Quantum Physics · Physics 2025-03-12 Salini Rajeev , Mayukh Lahiri

Conventional absorption spectroscopy relies on coherent laser sources, and in turn suffers from the inherent limitation of shot noise, especially in estimating weak absorption. Here we propose a measurement strategy with correlated photons…

Quantum Physics · Physics 2025-04-17 Zhucheng Zhang , Xue Zhang , Jing Liu , Hui Dong
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