Review
Quantum Science & Technology
Zhihui Yan, Liang Wu, Xiaojun Jia, Changde Xie, Kunchi Peng
Summary: A quantum network consists of quantum channels and quantum nodes, with the interaction between non-classical optical modes and quantum nodes, and quantum entanglement among multiple distant quantum nodes being essential building blocks. The practical applications of quantum network require multipartite non-classical states of optical modes that can directly interact with atomic ensembles, and a key goal is to unconditionally generate and store multipartite entangled states in atomic ensembles. Recent developments include creating multipartite continuous-variable polarization entangled optical modes and constructing a scalable quantum network with deterministic entanglement among multiple quantum memories.
ADVANCED QUANTUM TECHNOLOGIES
(2021)
Article
Engineering, Electrical & Electronic
Daryus Chandra, Angela Sara Cacciapuoti, Marcello Caleffi, Lajos Hanzo
Summary: This research proposes a novel quantum communication scheme that relies on realistic noisy pre-shared entanglement to eliminate the sequential steps causing delay in traditional methods, achieving superior performance by improving the quantum bit error ratio of logical qubits.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2022)
Article
Quantum Science & Technology
Carsten Blank, Adenilton J. da Silva, Lucas P. de Albuquerque, Francesco Petruccione, Daniel K. Park
Summary: Quantum computing offers exciting opportunities for kernel-based machine learning methods, allowing efficient construction of classifier models through quantum interference effects. To make these methods practical, it is important to minimize circuit size and handle imbalanced data sets.
QUANTUM SCIENCE AND TECHNOLOGY
(2022)
Article
Physics, Multidisciplinary
Daniel Martinez, Esteban S. Gomez, Jaime Carine, Luciano Pereira, Aldo Delgado, Stephen P. Walborn, Armin Tavakoli, Gustavo Lima
Summary: The most common measurement method in quantum mechanics is to project the wavefunction onto orthogonal states that correspond to definite outcomes. However, it is possible to have generalized quantum measurements that do not fully project quantum states, which play an important role in quantum information tasks. In this study, we demonstrate the robust realization of high-quality generalized measurements in higher-dimensional systems using multiport beamsplitters. We implemented a seven-outcome generalized measurement in a four-dimensional Hilbert space with a fidelity of 99.7% and showed that it cannot be simulated by any conceivable quantum protocol based on standard projective measurements.
Article
Optics
Julian Huber, Ana Maria Rey, Peter Rabl
Summary: This paper presents an efficient numerical method for simulating the dynamics of interacting spin ensembles in the presence of dephasing and decay. The method combines mean-field dynamics with a Monte Carlo sampling to account for quantum correlations, and can be applied to a variety of experiments in quantum optics or solid-state spin ensembles.
Article
Optics
K. S. Kravtsov
Summary: This paper analyzes the security aspects of practical entanglement-based quantum key distribution (QKD), such as the BBM92 or entanglement-based BB84 protocol. Like prepare-and-measure QKD protocols, the practical implementation of entanglement-based QKD relies on non-ideal photon sources. The spontaneous parametric down-conversion is a typical solution for entanglement generation, but it may create quantum states with more than two photons, potentially compromising security. However, this paper shows that this effect does not impair the security of entanglement-based QKD systems. The available security proofs also demonstrate that the properties of the entanglement source have no impact on security degradation.
LASER PHYSICS LETTERS
(2023)
Article
Quantum Science & Technology
Sowmitra Das, Md. Saifur Rahman, Mahbub Majumdar
Summary: Quantum communication relies on entanglement and quantum repeaters have been proposed to establish entanglement over large distances. Utilizing noisy quantum computers allows for emulation of the communication environment and assessment of protocol performance on real hardware. The circuit-level implementation of the quantum repeater architecture provides a benchmark for state-of-the-art quantum computing hardware.
QUANTUM INFORMATION PROCESSING
(2021)
Article
Optics
David S. Simon, Christopher R. Schwarze, Alexander Sergienko
Summary: This paper investigates the properties of Grover multiports interferometers and discovers that they have capabilities beyond traditional beam-splitter-based interferometers, such as easily controlled interpolation between Hong-Ou-Mandel and anti-HOM behavior, as well as simultaneous measurement of three independent phases.
Article
Optics
Danilo Zia, Nazanin Dehghan, Alessio D'Errico, Fabio Sciarrino, Ebrahim Karimi
Summary: Biphoton digital holography is a method that uses coincidence imaging to retrieve amplitude and phase information of an unknown biphoton state. This approach allows for a more efficient and reliable characterization of high-dimensional biphoton states. The proposed reconstruction technique achieves a three orders of magnitude faster measurement time and an average fidelity of 87% compared to previous experiments.
Article
Multidisciplinary Sciences
Hsuan-Hao Lu, Karthik Myilswamy, Ryan S. Bennink, Suparna Seshadri, Mohammed S. Alshaykh, Junqiu Liu, Tobias J. Kippenberg, Daniel E. Leaird, Andrew M. Weiner, Joseph M. Lukens
Summary: With the development of integrated biphoton frequency combs, quantum information processing in the frequency domain has attracted more attention in recent years. To address the scalability issue of frequency mixing operations, the authors propose a novel solution that utilizes pulse shapers and electro-optic phase modulators to perform random operations. They successfully verify the entanglement and reconstruct the full density matrix of biphoton frequency combs, achieving the highest dimension for frequency bins to date. The employed Bayesian statistical model can be tailored to various quantum systems with restricted measurement capabilities, providing an opportunistic tomographic framework.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
Shunzhong Xue, Yulei Huang, Dafa Zhao, Chao Wei, Jun Li, Ying Dong, Jiancun Gao, Dawei Lu, Tao Xin, Gui-Lu Long
Summary: In this study, parameterized quantum circuits are used to diagonalize density matrices of quantum states and measure entanglement by only measuring the diagonal elements. The proposed method has great potential in quantum systems with a large number of particles.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2022)
Article
Optics
Lin Cheng, Sheng-Chen Liu, Lei Geng, Yong-Kang Fang, Liang-You Peng
Summary: To implement a scalable and fault-tolerant programmable quantum computing architecture, high-fidelity, robust, and efficient quantum entangling gates are crucial. This paper proposes a geometrical hypersurface-tangent method to optimize the laser power and pulse gradient for segmented amplitude-modulated entangling gates. The method considers the experimental feasibility and allows for the optimization of solutions with a few segments. Additionally, it improves the robustness against various drifts.
Article
Physics, Multidisciplinary
Markus Hiekkamaki, Frederic Bouchard, Robert Fickler
Summary: The study combines the phase sensitivity of N00N states with the orbital angular momentum of photons to achieve high-resolution rotation detection. Results show that higher photon numbers and larger OAM enhance resolution and sensitivity, paving the way for angular supersensitivity and N00N state generation.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Shreya Kumar, Daniel Bhatti, Alex E. Jones, Stefanie Barz
Summary: Multipartite entanglement is essential in optical quantum technologies. This study demonstrates a simple and versatile scheme to generate different types of genuine tripartite entangled states using only one experimental setup. By sending three photons through a three-port splitter and varying their internal states, the generation of tripartite W, G, and GHZ states is achieved with high fidelities.
NEW JOURNAL OF PHYSICS
(2023)
Article
Physics, Multidisciplinary
Alejandro Pozas-Kerstjens, Nicolas Gisin, Armin Tavakoli
Summary: This paper introduces the concept of full network nonlocality and proves that it cannot be observed in the standard network Bell test. However, it is detectable in the generalization of star networks in quantum theory. Furthermore, the paper points out methods for analyzing full network nonlocality in any network and input-output scenario, and demonstrates their effectiveness through specific examples.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
Gil Triginer Garces, Helen M. Chrzanowski, Shakib Daryanoosh, Valerian Thiel, Anna L. Marchant, Raj B. Patel, Peter C. Humphreys, Animesh Datta, Ian A. Walmsley
APPLIED PHYSICS LETTERS
(2020)
Article
Physics, Multidisciplinary
Mankei Tsang, Francesco Albarelli, Animesh Datta
Article
Nanoscience & Nanotechnology
Vincent Dorier, Stephane Guerin, Hans-Rudolf Jauslin
Article
Physics, Multidisciplinary
Liang Xu, Zexuan Liu, Animesh Datta, George C. Knee, Jeff S. Lundeen, Yan-qing Lu, Lijian Zhang
PHYSICAL REVIEW LETTERS
(2020)
Article
Physics, Multidisciplinary
Ghassen Dridi, Kaipeng Liu, Stephane Guerin
PHYSICAL REVIEW LETTERS
(2020)
Article
Physics, Applied
Astghik Saharyan, Juan-Rafael Alvarez, Thomas H. Doherty, Axel Kuhn, Stephane Guerin
Summary: This study evaluates the exact dipole coupling strength between a single emitter and the radiation field within an optical cavity, considering the effects of multilayer dielectric mirrors. It is found that for very short cavities, the effective length used to determine their mode volume and the lengths defining their resonances differ significantly, with the radiation field being strongest within the dielectric mirror itself. Only for cavities much longer than their resonant wavelength does the mode volume asymptotically approach that normally assumed from their geometric length.
APPLIED PHYSICS LETTERS
(2021)
Article
Optics
M. Federico, V Dorier, S. Guerin, H. R. Jauslin
Summary: This article discusses a formulation in bosonic Fock space that directly constructs quantum excitations in the form of pulses. Compared to the expansion in plane waves, the pulse formulation has conceptual and practical advantages. By analyzing specific examples, the article demonstrates the advantages of the pulse formulation and identifies two essential elements related to photon behavior: the same shape of pulses and the bosonic nature of photons.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2022)
Article
Optics
Jing-jun Zhu, Xavier Laforgue, Xi Chen, Stephane Guerin
Summary: This study compares the dynamics and performance of robust inverse optimization and time-contracted adiabatic passage protocols, demonstrating the superiority of the former protocol.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2022)
Article
Physics, Multidisciplinary
Francois Peyraut, Frederic Holweck, Stephane Guerin
Summary: In this study, we investigate the problem of population transfer in a two-states system driven by an external electromagnetic field, considering a few cycles until the extreme limit of two or one cycle. By taking the physical constraint of zero-area total field into account, we determine strategies that lead to ultrahigh-fidelity population transfer, even when the rotating wave approximation fails. Specifically, we implement adiabatic passage based on adiabatic Floquet theory for as low as 2.5 cycles, finding and making the dynamics follow an adiabatic trajectory connecting the initial and targeted states. Additionally, nonadiabatic strategies with shaped or chirped pulses, extending the pi-pulse regime to two- or single-cycle pulses, are derived.
Article
Physics, Multidisciplinary
Raphael Couturier, Etienne Dionis, Stephane Guerin, Christophe Guyeux, Dominique Sugny
Summary: This article investigates the use of supervised learning to describe a two-level quantum system under an external time-dependent drive. The approach is applied to bang-bang control and the estimation of offset and final distance to a target state. A neural network is used to interpolate the mapping between offset and distance. Different neural network algorithms are tested, showing high precision in reproducing the mapping in the direct case while facing obstacles in the indirect case. The limits of the estimation procedure and the physical relevance of the results are discussed.
Article
Optics
Xavier Laforgue, Ghassen Dridi, Stephane Guerin
Summary: We study optimal quantum control strategies that are robust against pulse inhomogeneities for various partial population transfers and single-qubit gates using inverse optimization. We demonstrate that the pulse is constant for both time and energy minimization, and provide the analytical form of the detuning as Jacobi elliptic cosines. We compare the performance of composite pulse techniques optimized for complete population transfer to this optimal bound.
Article
Optics
Xavier Laforgue, Ghassen Dridi, Stephane Guerin
Summary: By applying the inverse geometric optimization technique, we have identified an optimal and robust method for generating stimulated Raman exact passage (STIREP) while considering the loss of the upper state. The optimized control field temporal shapes form a simple sequence with intuitively and counterintuitively ordered pulse pairs, resulting in significantly lower losses compared to the nonrobust optimal STIREP. Alternative optimal solutions with lower losses, larger pulse areas, and fully counterintuitive pulse sequences have also been derived.
Article
Physics, Multidisciplinary
Nicola Maraviglia, Patrick Yard, Ross Wakefield, Jacques Carolan, Chris Sparrow, Levon Chakhmakhchyan, Chris Harrold, Toshikazu Hashimoto, Nobuyuki Matsuda, Andrew K. Harter, Yogesh N. Joglekar, Anthony Laing
Summary: In this study, a programmable integrated photonic chip was used to simulate a model composed of PT-symmetric Hamiltonians. Quantum dynamics across exceptional points were simulated, showing the importance of programmable quantum simulators in investigating foundational questions in quantum mechanics.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Optics
Haixing Miao, Denis Martynov, Huan Yang, Animesh Datta
Article
Chemistry, Physical
Max Marcus, George C. Knee, Animesh Datta
FARADAY DISCUSSIONS
(2020)