Article
Quantum Science & Technology
Donghwa Lee, Young-Wook Cho, Hyang-Tag Lim, Sang-Wook Han, Hojoong Jung, Sung Moon, Yong-Su Kim
Summary: This study proposes a simple method to deduce the Bell state analyzer for single-photon inputs using weak coherent pulses, and experimentally verifies its feasibility and effectiveness in a Quantum Key Distribution protocol.
QUANTUM INFORMATION PROCESSING
(2021)
Article
Quantum Science & Technology
Lorenzo Stasi, Patrik Caspar, Tiff Brydges, Hugo Zbinden, Felix Bussieres, Rob Thew
Summary: Herald single-photon sources (HSPS) face the challenge of multiphoton emission, which requires a trade-off between single-photon quality and heralding rate. Photon-number-resolving (PNR) detectors are implemented to filter out heralding events with more than one photon pair, improving the HSPS.
QUANTUM SCIENCE AND TECHNOLOGY
(2023)
Article
Optics
Yansheng Bao, Bochen Wang, Qianhe Shao, Changyong Tian, Zhengyong Li
Summary: We demonstrate self-calibration of a photon-number-resolving (PNR) detector system to reduce PNR errors and optimize photon statistics distribution. Our method calibrates voltage ranges of the pulse height histogram corresponding to photon number states and optimizes photon statistics distribution without the need for standard detectors. The optimized photon statistics distributions agree with theoretical calculations and greatly reduce the relative errors of the average photon number compared to preliminary reconstruction. Our results are valuable for various PNR applications.
OPTICS COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
I. K. A. da Silva, F. A. Mendonca, R. V. Ramos
Summary: The article introduces an analytical expression for improving the performance of a multi-photon number resolving detector when measuring coherent states. By transforming the static MPNRD device into a dynamic one, it overcomes the impact of optical losses and non-unit quantum efficiency.
OPTICAL AND QUANTUM ELECTRONICS
(2023)
Article
Multidisciplinary Sciences
Shihan Sajeed, Poompong Chaiwongkhot, Anqi Huang, Hao Qin, Vladimir Egorov, Anton Kozubov, Andrei Gaidash, Vladimir Chistiakov, Artur Vasiliev, Artur Gleim, Vadim Makarov
Summary: This study introduces a security evaluation and improvement protocol for quantum communication systems, aiming to enhance security by subdividing systems and identifying potential loopholes.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Applied
Hao Hao, Qing-Yuan Zhao, Ling-Dong Kong, Shi Chen, Hui Wang, Yang-Hui Huang, Jia-Wei Guo, Chao Wan, Hao Liu, Xue-Cou Tu, La-Bao Zhang, Xiao-Qing Jia, Jian Chen, Lin Kang, Cong Li, Te Chen, Gui-Xing Cao, Pei-Heng Wu
Summary: Photon number resolving is crucial for detectors in quantum and classical applications. By utilizing a matched filter and a cryogenic amplifier, the performance of series PNR-SNSPD can be improved, achieving a maximum resolved photon number of 65 or even larger.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Inorganic & Nuclear
Natsumi Kimoto, Hiroaki Hayashi, Takumi Asakawa, Cheonghae Lee, Takashi Asahara, Tatsuya Maeda, Sota Goto, Yuki Kanazawa, Akitoshi Katsumata, Shuichiro Yamamoto, Masahiro Okada
Summary: This study introduces an effective method for determining atomic number (Z(eff)) based on a photon-counting technique, which corrects for beam hardening effect and detector response for high accuracy material identification. The method was demonstrated on X-ray images from an energy-resolving photon-counting detector, resulting in a Z(eff) image with an accuracy of Z(eff) +/- 0.5 regardless of mass thickness.
APPLIED RADIATION AND ISOTOPES
(2021)
Article
Quantum Science & Technology
M. T. DiMario, F. E. Becerra
Summary: In this article, we experimentally demonstrate the optimal inconclusive measurement using linear optics and single-photon detection to discriminate binary coherent states. We also propose a hybrid measurement that combines the optimal inconclusive measurement with sequential, unambiguous state elimination to achieve higher dimensional inconclusive measurements of coherent states.
NPJ QUANTUM INFORMATION
(2022)
Article
Optics
Shuo Li, Wenchao Li, Vladislav V. Yakovlev, Allison Kealy, Andrew D. Greentree
Summary: Achieving a fundamental understanding of biological pathways requires minimally invasive nanoscopic optical resolution imaging. In this study, a new approach is proposed by utilizing quantum measurements of photon number distributions to determine the number and probability of emission from single-photon emitters. This technique has great potential in quantum optical imaging with nanoscopic resolution.
Review
Nanoscience & Nanotechnology
Andreas J. Heinrich, William D. Oliver, Lieven M. K. Vandersypen, Arzhang Ardavan, Roberta Sessoli, Daniel Loss, Ania Bleszynski Jayich, Joaquin Fernandez-Rossier, Arne Laucht, Andrea Morello
Summary: Over the past three decades, nanoscience and quantum science have merged to create a new research field known as quantum-coherent nanoscience. This review focuses on the fundamental principles and practical applications of quantum coherence in nanoscale systems, as well as the challenges and opportunities ahead.
NATURE NANOTECHNOLOGY
(2021)
Article
Physics, Multidisciplinary
Dmitry A. Kuts, Mikhail S. Podoshvedov, Ba An Nguyen, Sergey A. Podoshvedov
Summary: We propose an efficient method to generate optical analogs of even and odd Schrodinger cat states with large amplitude, high fidelity, and reasonable generation rate.
Article
Multidisciplinary Sciences
Ruotian Gong, Guanghui He, Xingyu Gao, Peng Ju, Zhongyuan Liu, Bingtian Ye, Erik A. Henriksen, Tongcang Li, Chong Zu
Summary: In this study, we investigated the coherent dynamics of strongly interacting ensembles of negatively charged boron vacancy (V-B(-)) centers in hexagonal boron nitride (hBN). By selectively isolating different dephasing sources, we observed significant improvement in the measured coherence times and estimated the concentration of V-B(-). Additionally, we studied the spin response of V-B(-) to local charged defects induced electric field signals.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Applied
Kaori Hattori, Toshio Konno, Yoshitaka Miura, Sachiko Takasu, Daiji Fukuda
Summary: This study tested an Au/Ti (10/20 nm) bilayer TES that achieved a high energy resolution by lowering the critical temperature Tc to 115 mK. The results have important implications for improving the energy resolution in biological imaging and microscopic spectroscopy.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2022)
Article
Physics, Applied
Q. Pears Stefano, A. G. Magnoni, J. Estrada, C. Iemmi, D. Rodrigues, J. Tiffenberg
Summary: We have developed an imaging device in the infrared wavelength range that can arbitrarily reduce readout noise. The device has photon-number-resolving capability, high spatial resolution, high quantum efficiency in the near-infrared, and ultralow dark counts. By reducing the readout noise to less than 0.2e-, we are able to image objects in a broad range of intensities and reveal shapes previously hidden in the noise.
PHYSICAL REVIEW APPLIED
(2023)
Article
Optics
Yun-Fei Pu, Sheng Zhang, Yu-Kai Wu, Nan Jiang, Wei Chang, Chang Li, Lu-Ming Duan
Summary: An experiment successfully demonstrates the efficient connection of two quantum repeater segments via on-demand entanglement swapping using two atomic quantum memories with storage times of tens of milliseconds, showcasing the acceleration in scaling for a successful entanglement connection. This highlights a key advantage of the quantum repeater protocol and sets the stage for the development of future large-scale quantum networks.
Article
Optics
Aaron Z. Goldberg, Andrei B. Klimov, Hubert DeGuise, Gerd Leuchs, Girish S. Agarwal, Luis L. Sanchez-Soto
Summary: The study demonstrates that the multipoles associated with the density matrix can be unambiguously determined from intensity moments, and they have correct transformation properties, making them natural variables for dealing with various problems in the quantum domain.
Article
Nanoscience & Nanotechnology
Gerd Leuchs, Alexey Andrianov, Elena A. Anashkina, Alina A. Manshina, Peter Banzer, Markus Sondermann
Summary: Concentrating light requires suitable polarization patterns and 4 pi solid angle geometry for effective coupling with nanostructures. Cylindrical vector beams with specific patterns can be used to study nanostructures. The discussion also covers topics such as ultimate diffraction limit, resonant field enhancement, and nonresonant field enhancement.
Article
Optics
A. Andrianov, N. A. Kalinin, A. A. Sorokin, E. A. Anashkina, L. L. Sanchez-Soto, J. F. Corney, G. Leuchs
Summary: Bright squeezed light can be generated in optical fibers using the Kerr effect, but nonconservative effects degrade the squeezing. This study analyzes two-mode polarization squeezing, which is robust against perturbations and can be generated in a polarization-maintaining fiber. Numerical optimization and comparison with experimental results are performed using an advanced model of quantum pulse evolution in the fiber.
Article
Chemistry, Multidisciplinary
Anna A. A. Vasileva, Daria V. V. Mamonova, Yuri V. V. Petrov, Ilya E. E. Kolesnikov, Gerd Leuchs, Alina A. A. Manshina
Summary: We propose an efficient method for creating stable electrocatalytically active nanocomposites by combining in situ synthesis of polyaniline (PANI) with laser-induced deposition of metal nanoparticles (NPs). The use of the substrate during the formation of multi-metallic nanoparticles (MNP) solves the problem of particle loss from the electrode surface. The PANI/AgPt nanocomposites show the best activity and stability in electrocatalysis.
Article
Physics, Multidisciplinary
Jens A. H. Nielsen, Jonas S. Neergaard-Nielsen, Tobias Gehring, Ulrik L. Andersen
Summary: The modern scientific method relies on precise measurements of physical parameters. The measurement of optical phase, for example, is conventionally limited by the Heisenberg limit. However, deterministic phase estimation with N00N states has not yet reached or surpassed this limit. In this study, we use a scheme based on Gaussian squeezed vacuum states and high-efficiency homodyne detection to achieve phase estimates with extreme sensitivity that surpasses the shot noise limit and even the conventional Heisenberg limit.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Anna A. Vasileva, Daria V. Mamonova, Vladimir Mikhailovskii, Yuri V. Petrov, Yana G. Toropova, Ilya E. Kolesnikov, Gerd Leuchs, Alina A. Manshina
Summary: This paper presents a new methodology for creating 3D ordered porous nanocomposites using anodic aluminum oxide template with polyaniline (PANI) and silver NPs. The approach involves in situ synthesis of polyaniline on templates and laser-induced deposition of Ag NPs on the pore walls. The developed structures demonstrated effectiveness as non-enzymatic electrochemical sensors for glucose detection in a concentration range crucial for medical applications.
Article
Physics, Applied
M. A. T. Butt, P. Roth, G. K. L. Wong, M. H. Frosz, L. L. Sanchez-Soto, E. A. Anashkina, A. V. Andrianov, P. Banzer, P. St. J. Russell, G. Leuchs
Summary: Polarization-preserving fibers cannot preserve two nonorthogonal states required for quantum communication. We propose an alternative scheme using helically twisted photonic crystal fibers to enable polarization encoding in the continuous-variable regime. Experimental results show that appropriate nonorthogonal modes in the polarization-preserving fiber do not fully scramble over the full Poincare sphere, but remain on a great circle, forming a one-dimensional protected subspace that can be parametrized by a single variable. This allows for more efficient measurements of quantum excitations in nonorthogonal modes.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Multidisciplinary
Gerd Leuchs, Margaret Hawton, Luis L. Sanchez-Soto
Summary: This paper discusses the concept of emptiness in space and suggests changing the traditional view. It explores how vacuum fluctuations determine the values of permittivity and permeability by modeling their dynamic response using three-dimensional harmonic oscillators.
Article
Chemistry, Multidisciplinary
Gulia Bikbaeva, Anna Pilip, Anastasia Egorova, Ilya Kolesnikov, Dmitrii Pankin, Kirill Laptinskiy, Alexey Vervald, Tatiana Dolenko, Gerd Leuchs, Alina Manshina
Summary: Photopharmacology is an important and booming research area that requires new drugs with simultaneous photoswitching and pharmacophore functions. In this study, CQDs@phosphonate nanohybrids were introduced for the first time, which can inhibit butyrylcholinesterase and control inhibition degree through laser irradiation. This research has significant implications for the field of photopharmacology.
Article
Optics
Anders J. E. Bjerrum, Jonatan B. Brask, Jonas S. Neergaard-Nielsen, Ulrik L. Andersen
Summary: In this paper, an all-optical setup is analyzed, which achieves Bell-inequality violation over long distances by using probabilistic entanglement swapping. The setup consists of two-mode squeezers, displacements, beamsplitters, and on-off detectors. The arrangement of events to close both the detection and locality loopholes is described. A scenario with dichotomic inputs and outputs is analyzed, and the robustness of Bell inequality violation is checked for up to six parties, considering phase, amplitude, dark count noise, and loss.
Article
Optics
Anders J. E. Bjerrum, Jonatan B. Brask, Jonas S. Neergaard-Nielsen, Ulrik L. Andersen
Summary: This study investigates the storage and purification of a photon-loss-affected two-mode squeezed vacuum state using noiseless amplification with solid-state qubits. The proposed method increases entanglement between the parties sharing the state probabilistically. The amplification step involves transferring the state from an optical mode to a set of solid-state qubits acting as a quantum memory, similar to a set of quantum scissors.
Article
Optics
Frederik Werner Isaksen, Ulrik Lund Andersen
Summary: A mechanical system can be optimally controlled through continuous measurements of its position followed by feedback. Using the complete formalism, without invoking the standard rotating-wave approximation and the adiabatic approximation, we deduce the conditional and unconditional states of a mechanical oscillator that lead to mechanical cooling and mechanical squeezing. The exact solutions significantly differ from the approximate solutions, highlighting the importance of using the complete model. Additionally, we demonstrate that the conditional and unconditional states cannot coincide in a typical control scheme, even with infinite feedback strength.
Article
Quantum Science & Technology
Nikolay Kalinin, Thomas Dirmeier, Arseny A. Sorokin, Elena A. Anashkina, Luis L. Sanchez-Soto, Joel F. Corney, Gerd Leuchs, Alexey V. Andrianov
Summary: This paper reports on a new all-fiber setup for generating polarization squeezed light. The setup is composed of passive elements only, making it simple, stable, and easy to set up. More than 5 dB of directly measured squeezing is achieved over long periods of time without any adjustments. Therefore, this new scheme provides a robust and easy-to-set-up method for obtaining squeezed light applicable to various applications.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Quantum Science & Technology
Nicolas Fabre, Andrei B. Klimov, Gerd Leuchs, Luis L. Sanchez-Soto
Summary: This study proposes a new method to calculate the Wigner function for systems with SU(1,1) symmetry by utilizing the properties of the parity operator. It also presents an optical experiment that enables point-by-point sampling of the Wigner function.
AVS QUANTUM SCIENCE
(2023)
Review
Optics
Marie Ioannou, Bradley Longstaff, Mikkel Larsen, Jonas S. Neergaard-Nielsen, Ulrik L. Andersen, Daniel Cavalcanti, Nicolas Brunner, Jonatan Bohr Brask
Summary: High-quality randomness is crucial for secure information processing. This study presents a scheme for quantum randomness certification based on quantum steering. The scheme is one-sided device independent and can achieve high security with simple states and measurements. It is also immune to the detection loophole, making it the closest to full device independence using purely Gaussian states and measurements.
