Article
Optics
Senrui Chen, Sisi Zhou, Alireza Seif, Liang Jiang
Summary: We demonstrate that entangled measurements provide an exponential advantage in sample complexity for Pauli channel estimation, which is a fundamental problem and a necessary subroutine for benchmarking near-term quantum devices. Through our research, we provide an estimation protocol using ancilla that significantly reduces the number of copies of the Pauli channel required for accurate estimation. We also explore the benefits of a limited number of ancillas and how to apply the estimation protocol to practical quantum benchmarking tasks.
Article
Physics, Applied
V. F. Gili, C. Piccinini, M. Safari Arabi, P. Kumar, V Besaga, E. Brambila, M. Graefe, T. Pertsch, F. Setzpfandt
Summary: Quantum imaging is a research field that aims to enhance image reconstruction capabilities by exploiting the quantum nature of light. Despite successful demonstrations, quantum microscopy has been limited for practical applications due to various reasons. In this study, a method utilizing the quantum correlations of photon pairs and a scanning microscope is proposed for fast, single mode quantum imaging. The technique is tested on a metal grating to evaluate its resolution capabilities and demonstrated on onion epithelial cells, indicating its potential for scalable bio-physical quantum microscopy. The results, combined with advancements in photon-pair generation and detection technology, may enable the extension of quantum microscopy applications toward the mid-infrared region.
APPLIED PHYSICS LETTERS
(2022)
Article
Automation & Control Systems
Le Wang, Xianghui Cao, Bowen Sun, Heng Zhang, Changyin Sun
Summary: This article investigates the privacy issue of remote state estimation in cyber-physical systems and provides theoretical proof for the structural properties of optimal transmission schedules. Numerical simulation results are provided to validate the theoretical analysis.
IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS
(2021)
Article
Physics, Multidisciplinary
Mingkang Wang, Rui Zhang, Robert Ilic, Yuxiang Liu, Vladimir A. Aksyuk
Summary: Thermodynamic and quantum fluctuations impose limitations on measuring the accuracy of resonant frequency. Information theory can determine the minimum uncertainty of frequency in a method-independent way, providing a practical frequency estimator. The results have significance for frequency-based metrology across various physical domains.
COMMUNICATIONS PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
A. Lee Swindlehurst, Gui Zhou, Rang Liu, Cunhua Pan, Ming Li
Summary: This article examines channel estimation for passive RIS-based systems from a fundamental viewpoint, considering various scenarios and channel models, and conducts algorithm simulations and performance comparisons.
PROCEEDINGS OF THE IEEE
(2022)
Article
Optics
Philipp del Hougne, Remi Sobry, Olivier Legrand, Fabrice Mortessagne, Ulrich Kuhl, Matthieu Davy
Summary: The paper presents a blind and non-invasive wavefront shaping technique that provides optimal coupling to optical resonators by lengthening the delay times of waves, demonstrating coherent control of the incident wavefront in microwave experiments. This technique is expected to have important applications in enhancing light-matter interactions and energy harvesting in photonic materials.
LASER & PHOTONICS REVIEWS
(2021)
Article
Chemistry, Multidisciplinary
Chengkun Song, Le Zhao, Jiahao Liu, Wanjun Jiang
Summary: Magnetic skyrmions, as mobile topological spin textures, have been extensively discussed for their applications in racetrack memory devices. While the skyrmion Hall effect has been considered detrimental for constructing such devices, we demonstrate that it can be utilized to realize a three-terminal skyrmion circulator. The control of circulating direction is achieved by changing the sign of the topological charge. Our findings suggest the potential of incorporating the topological property of skyrmions for enabling novel spintronic functionalities, such as the skyrmion circulator.
Article
Physics, Multidisciplinary
Shexiang Jiang, Bao Zhao, Xingzhu Liang
Summary: This paper presents a three-dimensional controlled quantum teleportation scheme for an unknown single-qutrit state and analyzes it in terms of four types of noisy channels with memory. The results show that memory can enhance the average fidelity for trit-flip and t-depolarizing noises, but may become ineffective for t-phase-flip and trit-phase-flip noises above a certain noise threshold.
Article
Quantum Science & Technology
Ivana Mastroserio, Stefano Gherardini, Cosimo Lovecchio, Tommaso Calarco, Simone Montangero, Francesco S. Cataliotti, Filippo Caruso
Summary: The researchers have successfully achieved time-reversal operations using the dressed chopped random basis optimal control algorithm. Their findings demonstrate that by designing optimal modulated radio frequency fields, high-precision time-reversal transformations can be achieved in a Bose-Einstein condensate composed of non-interacting atoms. These results are expected to significantly advance the implementation of time-reversal operations in gate-based quantum computing.
ADVANCED QUANTUM TECHNOLOGIES
(2022)
Article
Neurosciences
Jan Morez, Filip Szczepankiewicz, Arnold J. den Dekker, Floris Vanhevel, Jan Sijbers, Ben Jeurissen
Summary: Tensor-valued diffusion encoding allows disentangling variations in diffusivity from microscopic anisotropy, orientation dispersion, and mixtures of multiple isotropic diffusivities. Two precision-optimized acquisition schemes are created to estimate the diffusion tensor distribution (DTD) parameters accurately and precisely. The weighted linear least squares (WLLS) estimator with the squared reciprocal of the predicted signal as weights outperforms conventional estimators in terms of accuracy and precision when appropriate constraints are used.
HUMAN BRAIN MAPPING
(2023)
Article
Automation & Control Systems
Ehsan Nekouei, Henrik Sandberg, Mikael Skoglund, Karl Henrik Johansson
Summary: This article studies the design of an optimal privacy-aware estimator for a public random variable based on noisy measurements, and analyzes the conditions for the optimal estimator to satisfy perfect privacy requirement.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Engineering, Electrical & Electronic
Guoying Zhu, Jisheng Dai, Chunqi Chang, Weichao Xu
Summary: This paper proposes a method to improve the uplink channel estimation performance in massive MIMO systems by exploiting channel sparsity. The success of the method lies in the independent application of variational Bayesian inference factorization and the sparse Bayesian learning framework, which effectively handle impulsive noise and decouple sparse signals from training signals.
DIGITAL SIGNAL PROCESSING
(2022)
Article
Optics
Matthew Ware, Guilhem Ribeill, Diego Riste, Colm A. Ryan, Blake Johnson, Marcus P. da Silva
Summary: This study demonstrates the implementation of Pauli-frame randomization in a superconducting circuit system to shape noise into more benign forms for quantum error correction and fault tolerance. By randomizing circuits, signatures of non-Markovian evolution are suppressed to statistically insignificant levels, while maintaining fidelity and even improving error rates. The randomization technique ensures rigorous statements about error properties and contributes to the scalability of quantum computing with imperfect qubits.
Article
Mathematics, Interdisciplinary Applications
Francois Chapeau-Blondeau
Summary: This paper explores the use of switched quantum channels with indefinite causal order for quantum phase estimation in the presence of noise. It extends previous explorations to include Pauli noises, which are important for qubits but have not been previously addressed. The results show that the presence and type of quantum noise are crucial in determining the nonstandard capabilities of the switched channel, with similarities to stochastic resonance phenomena.
FLUCTUATION AND NOISE LETTERS
(2023)
Article
Computer Science, Information Systems
Akash Kumar Mandal, Swades De
Summary: This letter proposes a novel statistical hybrid neural network (S-HNN) for estimating wireless communication channels contaminated by impulse noise. The S-HNN utilizes a convolutional neural network (CNN) to capture spatial fading characteristics and a long short-term memory (LSTM) network to extract temporal information. By employing finite lag samples and recycling the CNN-LSTM network, the proposed S-HNN framework outperforms existing channel estimation techniques in terms of reduced training length and time savings.
IEEE WIRELESS COMMUNICATIONS LETTERS
(2023)
Article
Quantum Science & Technology
M. Avesani, L. Calderaro, M. Schiavon, A. Stanco, C. Agnesi, A. Santamato, M. Zahidy, A. Scriminich, G. Foletto, G. Contestabile, M. Chiesa, D. Rotta, M. Artiglia, A. Montanaro, M. Romagnoli, V Sorianello, F. Vedovato, G. Vallone, P. Villoresi
Summary: The envisioned global quantum communication network will connect various nodes through optical fibers or free-space channels. The free-space segment must meet key requirements such as daytime operation and compatibility with existing fiber infrastructure. A prototype utilizing an integrated silicon-photonics chip for daylight quantum key distribution has been successfully tested in an urban setting, showing promise for future satellite missions.
NPJ QUANTUM INFORMATION
(2021)
Article
Engineering, Electrical & Electronic
Marco Avesani, Giulio Foletto, Matteo Padovan, Luca Calderaro, Costantino Agnesi, Elisa Bazzani, Federico Berra, Tommaso Bertapelle, Francesco Picciariello, Francesco B. L. Santagiustina, Davide Scalcon, Alessia Scriminich, Andrea Stanco, Francesco Vedovato, Giuseppe Vallone, Paolo Villoresi
Summary: Current technological progress is driving the commercial and worldwide expansion of Quantum Key Distribution, which can provide secure communication regardless of the computational power of attackers and will be a fundamental feature in future telecommunication networks. Through the implementation of a Quantum Key Distribution application on a classical fiber-based infrastructure, we have demonstrated the feasibility of low-cost and ready-to-use Quantum Key Distribution systems compatible with standard classical infrastructure.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Quantum Science & Technology
Alessia Scriminich, Giulio Foletto, Francesco Picciariello, Andrea Stanco, Giuseppe Vallone, Paolo Villoresi, Francesco Vedovato
Summary: This study presents a comprehensive model for evaluating the performance of a free-space ground-to-ground quantum key distribution system based on the efficient-BB84 protocol. The model takes into account various factors such as atmospheric channel, telescope design, quantum source and detector parameters, and provides a set of requirements and optimal design choices for a QKD system under specific channel conditions. The study highlights the importance of considering channel fluctuation statistics in correctly estimating the saturation rate of single-photon detectors.
QUANTUM SCIENCE AND TECHNOLOGY
(2022)
Review
Quantum Science & Technology
Makan Mohageg, Luca Mazzarella, Charis Anastopoulos, Jason Gallicchio, Bei-Lok Hu, Thomas Jennewein, Spencer Johnson, Shih-Yuin Lin, Alexander Ling, Christoph Marquardt, Matthias Meister, Raymond Newell, Albert Roura, Wolfgang P. Schleich, Christian Schubert, Dmitry V. Strekalov, Giuseppe Vallone, Paolo Villoresi, Lisa Woerner, Nan Yu, Aileen Zhai, Paul Kwiat
Summary: The Deep Space Quantum Link mission concept by NASA enables unique science experiments through robust quantum optical links. The principal experimental goals include long-range teleportation, tests of gravitational coupling to quantum states, and advanced tests of quantum nonlocality.
EPJ QUANTUM TECHNOLOGY
(2022)
Article
Physics, Multidisciplinary
Marco Avesani, Hamid Tebyanian, Paolo Villoresi, Giuseppe Vallone
Summary: The authors propose a Source-Device-Independent protocol that can simplify experimental implementation and increase the number of certified bits. They derive a tight lower-bound on the quantum conditional min-entropy using the POVM structure and experimental expectation values. The method is experimentally demonstrated using polarization-encoded qubits and multi-outcome POVM.
COMMUNICATIONS PHYSICS
(2022)
Article
Chemistry, Physical
Giulio Tavani, Chiara Barri, Erfan Mafakheri, Giorgia Franzo, Michele Celebrano, Michele Castriotta, Matteo Di Giancamillo, Giorgio Ferrari, Francesco Picciariello, Giulio Foletto, Costantino Agnesi, Giuseppe Vallone, Paolo Villoresi, Vito Sorianello, Davide Rotta, Marco Finazzi, Monica Bollani, Enrico Prati
Summary: Recent advancements in QKD protocols have explored the use of erbium-doped LEDs as nonlaser sources for quantum key distribution. Silicon LEDs based on electroluminescence of Er:O complexes in Si have been fabricated on a 220 nm SOI wafer. The Er:O diodes showed emission rates of 5 x 10^6 photons/s at 1550 nm at room temperature, and their integration on the SOI platform allows for the development of silicon photon sources suitable for arbitrary-statistic-tolerant QKD protocols.
Article
Chemistry, Analytical
Andrea Chiuri, Roberto Chirico, Federico Angelini, Fabrizio Andreoli, Ivano Menicucci, Marcello Nuvoli, Cristina Cano-Trujillo, Gemma Montalvo, Violeta Lazic
Summary: This article introduces a sensor called Crime Light Imaging (CLI) that is designed to perform high-resolution photography and visualization of latent traces at a distance of 2-10 meters. CLI combines high-power illumination LEDs and a color CMOS camera to detect fingerprints, blood, semen, and other traces, providing excellent image resolution and contrast enhancement. This represents a completely new approach in crime scene forensic examination.
Article
Quantum Science & Technology
Federico Berra, Costantino Agnesi, Andrea Stanco, Marco Avesani, Sebastiano Cocchi, Paolo Villoresi, Giuseppe Vallone
Summary: We propose a modular design for a Quantum Key Distribution (QKD) source using iPOGNAC, a stable and calibration-free polarization modulation scheme, for both intensity and polarization encoding. This source is resistant to security vulnerabilities such as side channels and quantum hacking attacks. Our intensity modulation scheme allows flexible adjustment of intensity ratio and reduces patterning effects. The source has been implemented and tested in the near-infrared band, making it suitable for satellite-based QKD. The modularity of the source simplifies development, testing, and qualification, especially for space missions. Our work paves the way for the development of second-generation QKD satellites with excellent performance at higher security levels.
EPJ QUANTUM TECHNOLOGY
(2023)
Article
Quantum Science & Technology
Massimiliano Guarneri, Ilaria Gianani, Marco Barbieri, Andrea Chiuri
Summary: Characterization of quantum objects through previous knowledge and the use of neural networks can lead to routine procedures for real-life components. In this study, a convolutional stage is introduced in a neural network to improve the tomographic estimate of parameters in quantum process tomography. The results demonstrate the viability of this approach as an effective tool operating on classical data produced by quantum systems.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Computer Science, Theory & Methods
Massimiliano Guarneri, Andrea Chiuri
Summary: Inferring the process matrix of a quantum channel is a crucial task in quantum information research. Traditional optimization methods have drawbacks, and this paper proposes an alternative approach based on neural networks, which denoises the process matrix by drawing an analogy with image pixels.
INTERNATIONAL JOURNAL OF QUANTUM INFORMATION
(2023)
Article
Quantum Science & Technology
Davide Scalcon, Costantino Agnesi, Marco Avesani, Luca Calderaro, Giulio Foletto, Andrea Stanco, Giuseppe Vallone, Paolo Villoresi
Summary: The robust implementation of quantum key distribution requires precise state generation, measurements, and optimal encoding. This study presents a cross-encoded scheme that achieves high accuracy quantum state generation and transmission through a self-compensating polarization modulator. The system demonstrates good and stable performance in terms of key and quantum bit error rates, and represents an important step towards the development of hybrid networks with fiber-optic and free-space links.
ADVANCED QUANTUM TECHNOLOGIES
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Marco Avesani, Luca Calderaro, Giulio Foletto, Costantino Agnesi, Francesco Picciariello, Francesco B. L. Santagiustina, Alessia Scriminich, Francesco Vedovato, Mujtaba Zahidy, Giuseppe Vallone, Paolo Villoresi
Summary: Quantum key distribution (QKD) is a mature and reliable quantum technology that enables two remote users to generate secret keys with unconditional security. This study presents a QKD field-trial over optical fibers in the city center of Padua, Italy, utilizing two key technologies developed by the group: a low-error, self-stabilized polarization encoder called iPOGNAC, and a novel synchronization technique called Qubit4Sync, which minimizes the experimental complexity of the system.
QUANTUM COMPUTING, COMMUNICATION, AND SIMULATION II
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Costantino Agnesi, Davide Scalcon, Marco Avesani, Luca Calderaro, Giulio Foletto, Andrea Stanco, Giuseppe Vallone, Paolo Villoresi
Summary: This paper presents a cross-encoded Quantum Key Distribution scheme, where state encoding is performed using a self-compensating and calibration-free polarization modulator, and transmission is done through time-bin encoding to resist perturbances from the fiber channel.
2022 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXHIBITION (OFC)
(2022)
Article
Optics
Giulio Foletto, Francesco Picciariello, Costantino Agnesi, Paolo Villoresi, Giuseppe Vallone
Summary: The decoy-state method is a standard enhancement to quantum key distribution protocols, but its theoretical foundation needs further study for new technological advancements. This work provides security bounds for decoy-state QKD using a source with an arbitrary photon emission statistic. The performance of the bounds is evaluated with three statistical distributions - Poisson, thermal, and binomial, showing that they are all viable options for QKD.
Article
Optics
A. Chiuri, I Gianani, V Cimini, L. De Dominicis, M. G. Genoni, M. Barbieri
Summary: Frequency correlations are a powerful tool for spectral analysis of difficult-to-measure objects. This study compares the metrological capabilities of quantum and classical ghost spectrometers and demonstrates the potential advantages of quantum ghost spectrometry.
