Article
Multidisciplinary Sciences
Mingjian He, Robert Malaney
Summary: In this study, a new CV-based teleportation protocol is explored to improve the transfer of hybrid entangled states. The modified protocol shows significant improvement over traditional CV teleportation for both DV qubits and CV qubits. Additionally, the use of non-Gaussian operations with quantum scissors provides the most improvement in loss tolerance.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Multidisciplinary
Martin Gaerttner, Tobias Haas, Johannes Noll
Summary: We present a general class of entanglement criteria for continuous variable systems based on the Husimi Q distribution, which allows for optimization over a set of concave functions. Our criteria have clear advantages under typical experimental constraints and can detect entanglement states that are undetectable by commonly used criteria.
PHYSICAL REVIEW LETTERS
(2023)
Article
Optics
Roohollah Ghobadi
Summary: This study investigates the role of nonclassical kernels in data distribution and parameter estimation, as well as the impact of imperfect state preparation, highlighting the importance of phase-space correlation functions in understanding the distinction between classical machine learning and quantum machine learning.
Article
Optics
Hossein Seifoory, Marc M. Dignam
Summary: We propose a general theoretical approach to model integrated sources of counterpropagating continuous-variable entangled states in lossy waveguides. By using a backward Heisenberg approach and solving the adjoint master equation, we are able to simulate the generation and propagation of the entangled state in the waveguide.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2022)
Article
Physics, Mathematical
Giovanni Ferrari, Ludovico Lami, Thomas Theurer, Martin B. Plenio
Summary: In this study, we examine asymptotic state transformations in continuous variable quantum resource theories. We prove that lower semicontinuity and strong superadditivity can be used to bound asymptotic transformation rates in these settings. We provide applications to optical nonclassicality, entanglement, and quantum thermodynamics resource theories. Our findings offer computable upper bounds for asymptotic transformation rates, including those achievable with linear optical elements.
COMMUNICATIONS IN MATHEMATICAL PHYSICS
(2023)
Article
Optics
Olena Kovalenko, Vladyslav C. Usenko, Radim Filip
Summary: Two-mode squeezed states are scalable and robust entanglement resources for quantum information protocols;
Optimizing initial squeezing, relative phase, and linear coupling can reduce the degradation of Gaussian entanglement in the presence of crosstalk;
Compensating crosstalk through mode interference improves the efficiency of using multimode continuous-variable photonic entanglement in quantum networks.
Article
Physics, Multidisciplinary
Ya-Dong Wu, Ge Bai, Giulio Chiribella, Nana Liu
Summary: Continuous-variable quantum information, encoded into infinite-dimensional quantum systems, is a promising platform for many quantum information protocols. It is essential to have reliable protocols for verifying multimode continuous-variable entangled states and devices, particularly in realistic scenarios where identical and independent operations cannot be guaranteed. This letter proposes the first set of protocols for verifying such states and devices in non-i.i.d scenarios, applicable to various types of quantum states and operations.
PHYSICAL REVIEW LETTERS
(2021)
Article
Optics
Olena Kovalenko, Young-Sik Ra, Yin Cai, Vladyslav C. Usenko, Claude Fabre, Nicolas Treps, Radim Filip
Summary: Quantum key distribution using continuous variables offers high-speed, low-noise homodyne detection and can achieve secure key transmission over long distances. Increasing system clock rates and frequency-mode-multiplexing can further enhance the secret key rate.
PHOTONICS RESEARCH
(2021)
Article
Optics
Shaoping Shi, Yajun Wang, Long Tian, Wei Li, Yimiao Wu, Qingwei Wang, Yaohui Zheng, Kunchi Peng
Summary: This article presents a fully connected continuous-variable quantum teleportation network architecture, where a squeezed state of light distributes entangled sideband modes to each communication link, offering potential for various tasks of quantum information processing.
LASER & PHOTONICS REVIEWS
(2023)
Article
Optics
Federico Andrea Sabattoli, Linda Gianini, Angelica Simbula, Marco Clementi, Antonio Fincato, Frederic Boeuf, Marco Liscidini, Matteo Galli, Daniele Bajoni
Summary: Researchers have successfully demonstrated an integrated source of frequency-entangled photon pairs on a silicon photonics chip, proving the existence of entanglement. This result opens up possibilities for on-chip integration of frequency-bin sources with other devices in the silicon photonics platform.
Article
Nanoscience & Nanotechnology
Zhen Jiang, Yizhou Ding, Chaoxiang Xi, Guangqiang He, Chun Jiang
Summary: The study demonstrates the topologically protected transport of continuous frequency entangled biphoton states using valley photonic crystals, with numerical simulations showing robustness against sharp bends and scattering. The proposal provides a concrete way to achieve topological protection of entangled quantum states operating at telecommunication wavelengths.
Article
Multidisciplinary Sciences
Tomohiro Yamazaki, Rikizo Ikuta, Toshiki Kobayashi, Shigehito Miki, Fumihiro China, Hirotaka Terai, Nobuyuki Imoto, Takashi Yamamoto
Summary: The research team successfully demonstrated a polarization entangled biphoton frequency comb (BFC) with over 1400 frequency modes, the largest number to date, by placing a specific waveguide resonator within a Sagnac loop. The polarization entanglement was verified through quantum state tomography with high fidelity in representative frequency mode groups.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Multidisciplinary
Ivan Supic, Joseph Bowles, Marc-Olivier Renou, Antonio Acin, Matty J. J. Hoban
Summary: Certifying quantum properties with minimal assumptions is a fundamental problem in quantum information science. Self-testing is a method to infer the underlying physics of a quantum experiment only from the measured statistics. We introduce a framework of network-assisted self-testing and use it to self-test any pure entangled quantum state of an arbitrary number of systems.
Article
Optics
Santiago Lopez-huidobro, Mohammad Noureddin, Maria Chekhova, Nicolas Y. JOLy
Summary: Researchers have successfully generated pairs of biphotons, one in the ultraviolet and its entangled partner in the infrared spectral range, using a xenon-filled single-ring photonic crystal fiber and four-wave mixing. By adjusting the gas pressure, the frequency of the biphotons can be tuned, with the ultraviolet photons ranging from 271 nm to 231 nm and their entangled partners ranging from 764 nm to 1500 nm. This breakthrough enables spectroscopy and sensing with undetected photons in the ultraviolet range.
Article
Physics, Multidisciplinary
Ivan Derkach, Vladyslav C. Usenko
Summary: The study shows that achieving quantum key distribution over satellite channels requires stable setup and reduction of noise and loss, with the key extraction method significantly affecting protocol robustness. Optimized signal squeezing can substantially improve protocol applicability, reducing system clock rates and aperture sizes compared to coherent-state protocols.
