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Visual Odometry (VO) and Visual SLAM (V-SLAM) systems often struggle in low-light and dark environments due to the lack of robust visual features. In this paper, we propose a novel active illumination framework to enhance the performance of…

Robotics · Computer Science 2025-09-09 Francesco Crocetti , Alberto Dionigi , Raffaele Brilli , Gabriele Costante , Paolo Valigi

In recent years, foundation models for monocular depth estimation have received increasing attention. Current methods mainly address typical daylight conditions, but their effectiveness notably decreases in low-light environments. There is…

Computer Vision and Pattern Recognition · Computer Science 2025-07-25 Longjian Zeng , Zunjie Zhu , Rongfeng Lu , Ming Lu , Bolun Zheng , Chenggang Yan , Anke Xue

We present the quantum theory of the measurement of bosonic particles by multipixel detectors. For the sake of clarity, we specialize on beams of photons. We study the measurement of different spatial beam characteristics, as position and…

Quantum Physics · Physics 2016-09-13 Vanessa Chille , Nicolas Treps , Claude Fabre , Gerd Leuchs , Christoph Marquardt , Andrea Aiello

Shadowgraphy is a technique widely used to diagnose objects or systems in various fields in physics and engineering. In shadowgraphy, an optical beam is deflected by the object and then the intensity modulation is captured on a screen…

Travelling modes of single-photon-added coherent states (SPACS) are characterized via optical homodyne tomography. Given a set of experimentally measured quadrature distributions, we estimate parameters of the state and also extract…

Quantum Physics · Physics 2013-04-01 S. N. Filippov , V. I. Man'ko , A. S. Coelho , A. Zavatta , M. Bellini

Spurious couplings and decoherence degrade the performance of solid-state quantum processors, demanding careful design, calibration, and mitigation protocols. These strategies often rely on characterization of the idling processor, but…

We study single-copy shadow tomography in the adversarial robust setting, where the goal is to learn the expectation values of $M$ observables $O_1, \ldots, O_M$ with $\varepsilon$ accuracy, but $\gamma$-fraction of the outcomes can be…

In this computational paper, we perform sensitivity analysis of long-time (or ensemble) averages in the chaotic regime using the shadowing algorithm. We introduce automatic differentiation to eliminate the tangent/adjoint equation solvers…

Dynamical Systems · Mathematics 2020-11-18 Nisha Chandramoorthy , Luca Magri , Qiqi Wang

The problem of efficient quantum state learning, also called shadow tomography, aims to comprehend an unknown $d$-dimensional quantum state through POVMs. Yet, these states are rarely static; they evolve due to factors such as measurements,…

Machine Learning · Computer Science 2024-09-18 Xinyi Chen , Elad Hazan , Tongyang Li , Zhou Lu , Xinzhao Wang , Rui Yang

In multimode optical systems, the spectral covariance matrix encodes all the information about quantum correlations between the quadratures of Gaussian states. Recent research has revealed that, in scenarios that are more common than…

Quantum Physics · Physics 2026-03-11 Bakhao Dioum , Virginia D'Auria , Giuseppe Patera

Verifying the proper preparation of quantum states is essential in modern quantum information science. Various protocols have been developed to estimate the fidelity of quantum states produced by different parties. Direct fidelity…

Quantum Physics · Physics 2024-12-11 Christopher Vairogs , Bin Yan

We propose and experimentally demonstrate non-destructive and noiseless removal (filtering) of vacuum states from an arbitrary set of coherent states of continuous variable systems. Errors i.e. vacuum states in the quantum information are…

Quantum Physics · Physics 2009-11-13 C. Wittmann , D. Elser , U. L. Andersen , R. Filip , P. Marek , G. Leuchs

Quantum process tomography is a critical capability for building quantum computers, enabling quantum networks, and understanding quantum sensors. Like quantum state tomography, the process tomography of an arbitrary quantum channel requires…

Quantum Physics · Physics 2023-05-26 Jonathan Kunjummen , Minh C. Tran , Daniel Carney , Jacob M. Taylor

Classical shadows are a versatile tool to probe many-body quantum systems, consisting of a combination of randomised measurements and classical post-processing computations. In a recently introduced version of the protocol, the…

Quantum Physics · Physics 2025-04-14 Riccardo Cioli , Elisa Ercolessi , Matteo Ippoliti , Xhek Turkeshi , Lorenzo Piroli

We present a shadow-tomography-enhanced Non-Orthogonal Quantum Eigensolver (NOQE) for more efficient and accurate electronic structure calculations on near-term quantum devices. By integrating shadow tomography into the NOQE, the…

In recent years, various shadow detection methods from a single image have been proposed and used in vision systems; however, most of them are not appropriate for the robotic applications due to the expensive time complexity. This paper…

Computer Vision and Pattern Recognition · Computer Science 2018-03-20 Sepideh Hosseinzadeh , Moein Shakeri , Hong Zhang

Properties of quantum systems can be estimated using classical shadows, which implement measurements based on random ensembles of unitaries. Originally derived for global Clifford unitaries and products of single-qubit Clifford gates,…

Quantum Physics · Physics 2023-09-25 Mirko Arienzo , Markus Heinrich , Ingo Roth , Martin Kliesch

We introduce Sketch Tomography, an efficient procedure for quantum state tomography based on the classical shadow protocol used for quantum observable estimations. The procedure applies to the case where the ground truth quantum state is a…

Quantum Physics · Physics 2026-05-27 Xun Tang , Haoxuan Chen , Yuehaw Khoo , Lexing Ying

As part of the effort to make use of squeezed states of light for detection of sub-shot-noise optical signals, we study the balanced heterodyne scheme, for which the corresponding spectral density of the photocurrent fluctuations produced…

Quantum Physics · Physics 2012-11-28 Sheng Feng , Zehuan Lu , Jie Zhang , Chenggang Shao

Most quantum key distribution (QKD) protocols can be classified as either a discrete-variable (DV) protocol or continuous-variable (CV) protocol, based on how classical information is being encoded. We propose a protocol that combines the…