Article
Physics, Multidisciplinary
Cheng Sheng, Jiayi Hou, Xiaodong He, Kunpeng Wang, Ruijun Guo, Jun Zhuang, Bahtiyar Mamat, Peng Xu, Min Liu, Jin Wang, Mingsheng Zhan
Summary: This study reports the first demonstration of two-dimensional dual-species atom assembly, achieved by rearranging initially randomly distributed atoms using a sorting algorithm and optical trapping technique. The resulting atom arrays have user-defined geometries and specific species ratios, making them highly attractive for applications in high-fidelity quantum logic, many-body quantum simulation, and single molecule array formation.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Stephen D. Erickson, Jenny J. Wu, Pan-Yu Hou, Daniel C. Cole, Shawn Geller, Alex Kwiatkowski, Scott Glancy, Emanuel Knill, Daniel H. Slichter, Andrew C. Wilson, Dietrich Leibfried
Summary: This study proposes and demonstrates a protocol for high-fidelity indirect readout of trapped ion hyperfine qubits. By mapping the state of one ion to a readout ion using laser-driven Raman transitions, the protocol reduces errors and allows for repetition to improve readout fidelity.
PHYSICAL REVIEW LETTERS
(2022)
Article
Quantum Science & Technology
Dong-Xu Chen, Junliang Jia, Pei Zhang, Chui-Ping Yang
Summary: This study presents two optimized architectures for effectively realizing arbitrary unitary transformations using photonic path and polarization. These architectures have significant importance in reducing the number of interferometers and transforming elementary operations.
QUANTUM SCIENCE AND TECHNOLOGY
(2023)
Article
Multidisciplinary Sciences
Andrei Tanasescu, David Constantinescu, Pantelimon George Popescu
Summary: The author proposed a distributed quantum computation protocol for small register devices, enabling the distribution of controlled unitary gates and leveraging quantum sharing of partial results for parallel processing, achieving for the first time the quantum distribution of very large gates using small register devices.
SCIENTIFIC REPORTS
(2022)
Review
Quantum Science & Technology
Huaijin Zhang, Xingyan Chen, Zhang-qi Yin
Summary: This article introduces the levitation of nanodiamonds and the basic physics of nitrogen-vacancy centers, explores methods for quantum information processing and precision measurement using these properties, and discusses applications in areas such as mass spectrometry and gravitational acceleration measurement.
ADVANCED QUANTUM TECHNOLOGIES
(2021)
Article
Optics
Fernando Martinez-Garcia, Lukas Gerster, Davide Vodola, Pavel Hrmo, Thomas Monz, Philipp Schindler, Markus Mueller
Summary: Studied the impact of calibration errors on the gate performance in the Mt lmer-St rensen entangling gate and verified the predictions through experiments.
Article
Optics
K. Sosnova, A. Carter, C. Monroe
Summary: For high-fidelity entangling gates based on transverse modes for mixed-species ion chains with large mass ratio, the laser power required is at least an order of magnitude higher than that for gates based on axial modes. Additionally, even with moderate mass differences, the transverse modes are much harder to cool than the axial modes.
Article
Computer Science, Hardware & Architecture
Nadia Nedjah, Sergio Raposo, Luiza de Macedo Mourelle
Summary: This work presents a novel approach to quantum computing by proposing a customizable hardware design of a dedicated processor that emulates the execution of quantum algorithms. The proposed hardware design overcomes the limitations of software-based simulators by utilizing parallelism and pipelined execution, delivering improved performance for emulating quantum algorithms. The architecture includes key components such as memories, computation unit, measurement unit, and control unit, which work together to efficiently execute quantum operations.
JOURNAL OF SUPERCOMPUTING
(2023)
Article
Computer Science, Information Systems
Michal Oszmaniec, Adam Sawicki, Michal Horodecki
Summary: In this work, quantitative connections between epsilon-nets and approximate unitary t-designs are studied, revealing their relationship in d-dimensional Hilbert space and their applications in quantum computing. The results show near optimality and the potential for new construction methods in quantum computing.
IEEE TRANSACTIONS ON INFORMATION THEORY
(2022)
Article
Optics
Hao Song, Kaiheng Zou, Huibin Zhou, Narek Karapetyan, Amir Minoofar, Xinzhou Su, Ahmed Almaiman, Jonathan L. Habif, Moshe Tur, Alan E. Willner
Summary: This paper experimentally demonstrates an optics-based half-adder for two 4-phase-shift-keying (4-PSK) data channels using nonlinear wave mixing. The half-adder has high conversion efficiency and low optical signal-to-noise ratio (OSNR).
Article
Optics
Anupam Mitra, Sivaprasad Omanakuttan, Michael J. Martin, Grant W. Biedermann, Ivan H. Deutsch
Summary: This paper revisits the implementation of a two-qubit entangling gate called Mt lmer-St rensen gate using adiabatic Rydberg dressing for neutral atoms. The study shows that rapid adiabatic passage can be achieved through a two-photon transition without the need for an ultraviolet laser, by simply modulating the amplitude of one field with fixed laser frequencies. The results demonstrate that entangling gate fidelities comparable to the one-photon excitation can be achieved with the two-photon excitation. Furthermore, the paper explores how the adiabatic dressing protocol can be used to implement entangling gates beyond the regime of a perfect Rydberg blockade, allowing for fast high-fidelity gates for atoms separated beyond the blockade radius.
Article
Optics
Dong-Xu Chen, Yunlong Wang, Feiran Wang, Jun-Long Zhao, Chui-Ping Yang
Summary: High-dimensional quantum systems have advantages over low-dimensional ones, but unitary transformations on quantum states become technically infeasible as the dimensionality increases. Photonic orbital angular momentum (OAM) provides a natural carrier to encode information in high-dimensional spaces. This work proposes an efficient scheme to realize arbitrary unitary transformations on the path-OAM coupled quantum states by combining the path and OAM degrees of freedom of a single photon. It reduces the number of required interferometers while maintaining the symmetric structure, and can be used to manipulate the photonic OAM states.
LASER & PHOTONICS REVIEWS
(2023)
Article
Physics, Multidisciplinary
Gui-Long Jiang, Hai-Rui Wei, Guo-Zhu Song, Ming Hua
Summary: The authors propose a quantum circuit model for implementing complex quantum computation. They show that certain gates and rotations can simulate controlled-unitary gates and diagonal unitary gates. The quantum circuits for implementing the target gates are also presented.
ANNALEN DER PHYSIK
(2022)
Article
Engineering, Electrical & Electronic
Francesco Maria Puglisi, Tommaso Zanotti, Paolo Pavan
Summary: This paper proposes a new synthesis method for implication logic circuits based on memristors by revisiting Boole's expansion theorem. The method optimizes the operation sequence and reduces the number of memristors, while leveraging well-established logic circuit optimization methods. It outperforms existing approaches and allows for a fair comparison between CMOS and implication logic implementations under the same level of optimization, with possible device-circuit co-design strategies discussed for optimizing circuit performance.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS
(2021)
Article
Automation & Control Systems
Sheh-Yi Sheu, Hua-Yi Hsu, Dah-Yen Yang
Summary: DNA, RNA, and protein are demonstrated as promising media for QCs, using residue pairs for quantum logic gates via proton-coupled electron transfer. Transfer of protons between donor and acceptor states fulfill qubits, with specific pairs obeying Toffoli, SWAP, and CNOT gates, while amino acids achieve 1-qubit and satisfy Pauli-X, -Y, and -Z gates. Universal quantum logic gate generators are obtained.
ADVANCED INTELLIGENT SYSTEMS
(2021)
Article
Optics
Jiayi Qin, Giovanni Guccione, Jinyong Ma, Chenyue Gu, Ruvi Lecamwasam, Ben C. Buchler, Ping Koy Lam
Summary: This paper investigates the influence of photothermal properties on optomechanical instability in an optomechanical cavity and proposes a method to control system dynamics by changing the sign of photothermal interaction, achieving stable equilibrium. The research is of significant importance for optical control and precise metrological applications, especially for high-sensitivity resonating systems that are affected by photothermal effects.
Article
Multidisciplinary Sciences
Lorcan O. Conlon, Thibault Michel, Giovanni Guccione, Kirk McKenzie, Syed M. Assad, Ping Koy Lam
Summary: Satellite geodesy is a technique that uses satellite motion measurements to estimate accurate information about Earth's gravitational field. This study focuses on the precision limits of such measurements by examining approximate models for three main noise sources in the measurement process of the GRACE Follow-On mission: laser phase noise, accelerometer noise, and quantum noise. The study shows that the removal of laser phase noise through time-delay interferometry can significantly improve the signal-to-noise ratio. Furthermore, the use of differential mass satellite formations can further enhance the signal-to-noise ratio by eliminating accelerometer noise. Additionally, the study suggests that techniques from quantum optics can reduce quantum noise in alternative mission configurations. The proposed methods have the potential to greatly enhance the performance of future satellite geodesy missions.
Article
Physics, Multidisciplinary
Anthony C. Leung, K. S. Ida Melody, Aaron D. Tranter, Karun Paul, Geoff T. Campbell, Ping Koy Lam, Ben C. Buchler
Summary: Researchers propose a scheme based on gradient echo memory to achieve strong nonlinear interactions between single photons in cold atomic ensembles, overcoming the limitations caused by spontaneous emission. The effectiveness of the scheme is experimentally demonstrated, and strategies to address the degradation of memory efficiency caused by large phase shifts are presented.
NEW JOURNAL OF PHYSICS
(2022)
Article
Optics
Biveen Shajilal, Oliver Thearle, Aaron Tranter, Yuerui Lu, Elanor Huntington, Syed Assad, Ping Koy Lam, Jiri Janousek
Summary: This paper presents a bow-tie optical parametric amplifier (OPA) for generating squeezed vacuum states, which exhibits high squeezing levels and long-term stability. It has potential applications in various quantum fields.
Article
Physics, Multidisciplinary
Lorcan O. Conlon, Tobias Vogl, Christian D. Marciniak, Ivan Pogorelov, Simon K. Yung, Falk Eilenberger, Dominic W. Berry, Fabiana S. Santana, Rainer Blatt, Thomas Monz, Ping Koy Lam, Syed M. Assad
Summary: Entanglement, a fundamental feature of quantum mechanics, shows great potential for enhancing metrology and communications. Current focus in quantum metrology has been on generating highly entangled states for improved sensitivity. However, to achieve ultimate limits in multi-parameter quantum metrology and information processing, collective measurements that generate entanglement between multiple copies of quantum states are necessary. Optimal single and two-copy collective measurements for estimating non-commuting qubit rotations have been experimentally demonstrated, enabling quantum-enhanced sensing even under high decoherence levels and providing insights into the uncertainty principle. Superconducting, trapped-ion, and photonic systems were used to implement these optimal measurements, giving a glimpse into future quantum-enhanced sensing networks.
Article
Quantum Science & Technology
Ozlem Erkilic, Lorcan Conlon, Biveen Shajilal, Sebastian Kish, Spyros Tserkis, Yong-Su Kim, Ping Koy Lam, Syed M. M. Assad
Summary: Decoherence is a problem for quantum key distribution (QKD) over long distances. This paper proposes the use of quantum repeaters to minimize the effects of losses in the channel by dividing the total distance between users into smaller segments. A measurement-device-independent protocol is introduced, which uses high-dimensional states prepared by two trusted parties and a coherent total photon number detection for entanglement swapping at the repeater station. The experimentally feasible protocol achieves better key rates and longer transmission distance compared to existing protocols, surpassing the fundamental limit of repeaterless bound even at a shorter distance than existing TF-QKD protocols.
NPJ QUANTUM INFORMATION
(2023)
Article
Physics, Multidisciplinary
Lorcan O. Conlon, Ping Koy Lam, Syed M. Assad
Summary: This study compares the performance of single- and two-qubit probes for estimating multiple phase rotations under different noisy channels, showing that two-qubit probes exhibit enhanced parameter estimation capabilities. Entanglement is required in both the state preparation and state measurement stages to reach the ultimate precision limits allowed by quantum mechanics.
Article
Multidisciplinary Sciences
Jie Zhao, Hao Jeng, Lorcan O. Conlon, Spyros Tserkis, Biveen Shajilal, Kui Liu, Timothy C. Ralph, Syed M. Assad, Ping Koy Lam
Summary: This article presents a protocol that uses heralded noiseless amplification to increase the fidelity of continuous-variable quantum teleportation. The method allows for high-fidelity teleportation of coherent states and purification of thermalized input states, overcoming long-standing hurdles in continuous-variable quantum teleportation. These results have both practical and fundamental significance.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Bohan Li, Aritra Das, Spyros Tserkis, Prineha Narang, Ping Koy Lam, Syed M. Assad
Summary: The maximum entanglement achievable through passive transformations by continuous-variable states is called the entanglement potential. Recent research indicates that the entanglement potential can be upper-bounded by a simple function of squeezing of formation. Certain classes of two-mode Gaussian states can saturate this bound, but it remains an open problem for the general case. In this study, a larger class of states is introduced that is proven to saturate the bound, and it is conjectured that all two-mode Gaussian states can be passively transformed into this class, thereby equating entanglement potential with squeezing of formation. An explicit algorithm for the passive transformations is provided, and extensive numerical testing is performed to support this claim, aiming to unify the resource theories of two characteristic quantum properties of continuous-variable systems.
SCIENTIFIC REPORTS
(2023)
Article
Optics
Wanli Xing, T. C. Ralph
Summary: We have derived analytical solutions for the Heisenberg evolution under the trilinear parametric Hamiltonian, which are accurate up to second order in the interaction strength and valid for all pump amplitudes. These solutions enable the incorporation of pump depletion effects in the description of optical parametric amplification in experimentally relevant scenarios and provide a rigorous description of the resulting phenomena.
Article
Optics
Caroline Mauron, Timothy C. Ralph
Summary: We analyze and compare three quantum communication protocols proposed in the literature for their ability to transmit single-rail entanglement. Specific metrics are used to measure output-state purity and probability of success, taking into account the imperfections of photon source and detection components. Our findings suggest that, under most conditions, a distributed noiseless linear amplification (NLA) protocol with a relay point placed halfway between Alice and Bob outperforms NLA at Bob's end and a recently proposed purification protocol, unless the distance is very small or the photon source component is of high quality.
Proceedings Paper
Instruments & Instrumentation
Georg Enzian, Lars Freisem, John J. Price, Andreas O. Svela, Jack Clarke, Magdalena Szczykulska, Joshua Nunn, Ian Walmsley, Jonathan Silver, Leonardo Del Bino, Shuangyou Zhang, Pascal Del'Haye, Biveen Shajilal, Jiri Janousek, Ben C. Buchler, Ping Koy Lam, Michael R. Vanner
Summary: Research on backward Brillouin scattering in whispering-gallery-mode micro-resonators provides a promising avenue for both classical and quantum optomechanics applications. Our team, in collaboration with others, is utilizing this regime to prepare non-Gaussian motional states of the acoustic field. Recent experimental results include Brillouin optomechanical strong coupling, manipulation of thermal states by adding or subtracting single phonons, and phase-space tomography of non-Gaussian states generated by subtracting single or multiple phonons.
OPTICAL AND QUANTUM SENSING AND PRECISION METROLOGY II
(2022)
