Article
Multidisciplinary Sciences
J. Randall, C. E. Bradley, F. van der Gronden, A. Galicia, M. H. Abobeih, M. Markham, D. J. Twitchen, F. Machado, N. Y. Yao, T. H. Taminiau
Summary: The study observes characteristic features of the many-body-localized discrete time crystal (DTC) using a quantum simulation platform, demonstrating long-lived period-doubled oscillations and showing time-crystalline order across the many-body spectrum. The results are consistent with the realization of an out-of-equilibrium Floquet phase of matter and introduce a programmable quantum simulator based on solid-state spins for exploring many-body physics.
Article
Multidisciplinary Sciences
Pavel Hrmo, Benjamin Wilhelm, Lukas Gerster, Martin W. van Mourik, Marcus Huber, Rainer Blatt, Philipp Schindler, Thomas Monz, Martin Ringbauer
Summary: Quantum information carriers naturally occupy high-dimensional Hilbert spaces, and high-dimensional (qudit) quantum systems are becoming a powerful resource for quantum processors. Generating the desired interaction efficiently in these systems is crucial. In this study, the authors demonstrate the implementation of a native two-qudit entangling gate up to dimension 5 in a trapped-ion system. They use a light-shift gate mechanism to generate genuine qudit entanglement in a single application of the gate, which seamlessly adapts to the local dimension of the system with a calibration overhead independent of the dimension. Native entangling techniques for qudits are important for encoding quantum information.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Grigory E. Astrakharchik, Luis A. Pena Ardila, Krzysztof Jachymski, Antonio Negretti
Summary: In this study, using quantum Monte Carlo methods, we investigate the static properties of two ionic impurities in a bosonic bath and identify three bipolaronic regimes. We further reveal strong bath-induced interactions between the two ionic polarons. Our findings demonstrate the necessity of numerical simulations in describing highly correlated impurity models.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Multidisciplinary
B. -W. Li, Q. -X. Mei, Y. -K. Wu, M. -L. Cai, Y. Wang, L. Yao, Z. -C. Zhou, L. M. Duan
Summary: This study reports the quantum simulation of the JCH model using trapped ions. By engineering low excitations and low effective dimensions, the simulation results are verified even for large ion numbers. By treating the phonon modes as baths, the Markovian or non-Markovian spin dynamics in different parameter regimes of the JCH model are explored, similar to quantum emitters in a structured photonic environment. The dependence of non-Markovian dynamics on the effective Hilbert space dimension is also examined.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Eli Chertkov, Justin Bohnet, David Francois, John Gaebler, Dan Gresh, Aaron Hankin, Kenny Lee, David Hayes, Brian Neyenhuis, Russell Stutz, Andrew C. Potter, Michael Foss-Feig
Summary: An experiment with a trapped-ion quantum processor demonstrates the efficient simulation of the evolution of infinite entangled states using holographic technique and quantum tensor-network methods. The results show excellent quantitative agreement with theoretical predictions, indicating the potential of practical quantum computational advantage in science and technology.
Article
Multidisciplinary Sciences
J. M. Pino, J. M. Dreiling, C. Figgatt, J. P. Gaebler, S. A. Moses, M. S. Allman, C. H. Baldwin, M. Foss-Feig, D. Hayes, K. Mayer, C. Ryan-Anderson, B. Neyenhuis
Summary: The QCCD proposal outlines a blueprint for a universal quantum computer using mobile ions as qubits, limiting quantum interactions to small ion crystals to maintain low error rates demonstrated in small experiments. The integration of necessary elements into a programmable trapped-ion quantum computer has led to the realization of a teleported CNOT gate with negligible crosstalk error and high quantum volume, showing the potential for high-performance quantum computers.
Article
Multidisciplinary Sciences
Philipp T. Dumitrescu, Justin G. Bohnet, John P. Gaebler, Aaron Hankin, David Hayes, Ajesh Kumar, Brian Neyenhuis, Romain Vasseur, Andrew C. Potter
Summary: Emerging programmable quantum simulation platforms provide unprecedented access to far-from-equilibrium quantum many-body dynamics in isolated systems. This study demonstrates a dynamically protected topological phase in a quasiperiodically driven array of ten Yb-171(+) hyperfine qubits. The phase exhibits edge qubits that are immune to control errors and external perturbations, relying on emergent dynamical symmetries. This work paves the way for implementing more complex dynamical topological orders that enable error-resilient manipulation of quantum information.
Article
Physics, Multidisciplinary
Parth Raina, Bodhaditya Santra
Summary: This study analyzes various multi-level Rydberg excitation schemes to suppress motional dephasing in optically trapped Cesium atom qubits, determining the characteristics of a three-level system that can be used to eliminate dephasing. These systems can be directly employed in state-of-the-art quantum simulation and quantum computation experiments to reduce trap induced decoherence. This research paves the way for large scale quantum information processing architecture using optically trapped alkali atom qubits.
Article
Physics, Multidisciplinary
Reinhold Blumel, Nikodem Grzesiak, Nhung H. Nguyen, Alaina M. Green, Ming Li, Andrii Maksymov, Norbert M. Linke, Yunseong Nam
Summary: To scale up quantum processors and achieve quantum advantage, a new gate-optimizing principle has been introduced to trade off negligible amounts of gate fidelity for substantial savings in power, leading to significant increases in gate speed and/or qubit connectivity. This method has been experimentally verified on a trapped-ion quantum computer and provides increased robustness to mode drift.
PHYSICAL REVIEW LETTERS
(2021)
Article
Optics
Lorenzo Oghittu, Melf Johannsen, Antonio Negretti, Rene Gerritsma
Summary: The study investigates the quantum dynamics of an ion interacting with either a Bose or spin-polarized Fermi gas in a radio-frequency trap. The research considers quantum optical master equations under weak coupling and Lamb-Dicke approximations. Results show that ion dynamics are influenced by the quantum statistics of the gas, with lower ionic energies achievable with a fermionic gas.
Article
Quantum Science & Technology
Nikodem Grzesiak, Andrii Maksymov, Pradeep Niroula, Yunseong Nam
Summary: This article discusses the importance of parallel operations in quantum computing and the advantages of EASE gates. By implementing EASE gates in parallel, efficient quantum circuits can be realized on trapped-ion quantum computers, which is significant for quantum chemistry simulations and pattern matching algorithms.
Article
Physics, Multidisciplinary
Milajiguli Rexiti, Laleh Memarzadeh, Stefano Mancini
Summary: This paper addresses the problem of dephasing channel discrimination for finite-dimensional systems. Analytical solutions are provided for the optimization of input states without energy constraint for qubit, qutrit and ququart. Additionally, it is shown that resorting to side entanglement assisted strategy is completely useless in this case.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Quantum Science & Technology
M. Malinowski, D. T. C. Allcock, C. J. Ballance
Summary: This paper addresses the wiring challenge of trapped-ion quantum computers by introducing the WISE architecture. The WISE architecture integrates simple switching electronics into the ion-trap chip, reducing the I/O requirements without compromising performance. By using the WISE architecture, a fully connected 1000-qubit trapped-ion quantum computer can be operated at a speed of approximately 40-2600 quantum gate layers per second.
Article
Chemistry, Physical
Ke Sun, Chao Fang, Mingyu Kang, Zhendian Zhang, Peng Zhang, David N. N. Beratan, Kenneth R. R. Brown, Jungsang Kim
Summary: This study presents a quantum simulation method to investigate the impact of light polarization on electron transfer between molecules. By controlling the quantum states of trapped atomic ions, we can simulate electron transfer dynamics resembling those in molecules. Using three-level systems instead of traditional two-level systems enhances simulation efficiency and fidelity. We analyze the transfer efficiency by considering the quantum interference of electron coupling pathways and examine potential error sources in the quantum simulations. Trapped-ion systems offer favorable scalability compared to classical computers, enabling richer electron transfer simulations.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Physics, Fluids & Plasmas
Saikat Mondal, Sourav Bhattacharjee
Summary: In this study, we investigate the charging of a quantum battery by modulating the Hamiltonian and find that resonance tunneling at specific drive frequencies can enhance energy transfer and improve energy storage stability. Breaking the integrability allows for global charging of the battery, but there is no quantum advantage in terms of charging power.
Article
Optics
Alexander Luce, Ali Mahdavi, Florian Marquardt, Heribert Wankerl
Summary: This article introduces a Python package for calculating optical reflection and transmission in multilayer thin film structures, which provides fast parallel computation for experimentation with new optimization techniques, generation of datasets for machine learning, and effective evolutionary optimization. Additionally, an OpenAI Gym environment is provided for training reinforcement learning agents on the problem of finding multilayer thin-film configurations.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION
(2022)
Article
Multidisciplinary Sciences
Juliane Doster, Tirth Shah, Thomas Foesel, Philipp Paulitschke, Florian Marquardt, Eva M. Weig
Summary: Nanomechanics has matured as a field, with coupled nanomechanical resonator arrays serving as important model systems for studying collective dynamics. In this study, a two-dimensional array of pillar resonators encoding a mechanical polarization degree of freedom was introduced to analyze polarization patterns and identify topological singularities.
NATURE COMMUNICATIONS
(2022)
Article
Quantum Science & Technology
Barbara Andrade, Zohreh Davoudi, Tobias Grass, Mohammad Hafezi, Guido Pagano, Alireza Seif
Summary: Trapped-ion quantum simulators utilizing the Molmer-Sorensen scheme to induce three-spin interactions are studied. The scheme allows for tailored single-, two-, and three-spin interactions and can be tuned for purely three-spin dynamics simulation. Analytical results and numerical simulations support the accuracy and feasibility of the scheme for near-term applications. The advantage of direct analog implementation of three-spin dynamics is demonstrated, and strategies for scaling the scheme to larger systems are discussed.
QUANTUM SCIENCE AND TECHNOLOGY
(2022)
Article
Multidisciplinary Sciences
Hengjiang Ren, Tirth Shah, Hannes Pfeifer, Christian Brendel, Vittorio Peano, Florian Marquardt, Oskar Painter
Summary: This article reports the realization of topological phonon transport in an optomechanical device and introduces the design and measurement results of the experiment. This study represents a significant advancement in the field of downscaled mechanical topological systems.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
Yao-Tong Chen, Lei Du, Lingzhen Guo, Zhihai Wang, Yan Zhang, Yong Li, Jin-Hui Wu
Summary: This research explores the nonreciprocity of giant atoms and proposes a scheme of coupling giant atoms to waveguides to build efficient single-photon targeted routers and circulators. The study investigates the nontrivial single-photon scattering properties of giant atoms as an effective platform for nonreciprocal and chiral quantum optics.
COMMUNICATIONS PHYSICS
(2022)
Review
Physics, Applied
Valentin Gebhart, Raffaele Santagati, Antonio Andrea Gentile, Erik M. Gauger, David Craig, Natalia Ares, Leonardo Banchi, Florian Marquardt, Luca Pezze, Cristian Bonato
Summary: Although the complexity of quantum systems increases exponentially with their size, classical algorithms and optimization strategies still play a crucial role in characterizing and detecting quantum states and dynamics. The future of quantum technologies relies on developing complex quantum systems for computation, simulation, and sensing, which poses challenges in control, calibration, and validation. This review explores classical post-processing techniques and adaptive optimization approaches to learn about quantum systems, their correlations, dynamics, and interaction with the environment, using various qubit architectures such as spin qubits, trapped ions, photonic and atomic systems, and superconducting circuits. It also highlights the importance of Bayesian formalism and neural networks.
NATURE REVIEWS PHYSICS
(2023)
Article
Computer Science, Artificial Intelligence
Alexander Luce, Ali Mahdavi, Heribert Wankerl, Florian Marquardt
Summary: In this research, the authors use a conditional invertible neural network (cINN) to design multilayer thin-films based on an optical target. The cINN is trained to learn the loss landscape of all thin-film configurations within a training dataset, allowing it to generate proposals for thin-film configurations that are close to the desired target. By further refining these proposals through local optimization, the generated thin-films achieve the target with greater precision compared to existing approaches. The cINN also demonstrates the ability to predict thin-films for out-of-distribution targets.
MACHINE LEARNING-SCIENCE AND TECHNOLOGY
(2023)
Article
Optics
Lei Du, Lingzhen Guo, Yong Li
Summary: Giant atoms serve as a promising platform for engineering decoherence-free interactions in quantum technologies. This study explores the implementation of complex decoherence-free interactions among giant atoms using periodic coupling modulations and suitable arrangements of coupling points. The results show that the modulation phase can be encoded into the interactions, enabling phase-dependent dynamics when the giant atoms form a closed loop. Additionally, the influence of non-Markovian retardation effect arising from large separations of coupling points is also considered, along with its dependence on the modulation parameters.
Article
Optics
Mario Krenn, Jonas Landgraf, Thomas Foesel, Florian Marquardt
Summary: In recent years, the rapid development in machine learning has had a significant impact on various fields of science and technology. This perspective article explores how quantum technologies are benefiting from this revolution. It showcases how scientists have utilized machine learning and artificial intelligence to analyze quantum measurements, estimate parameters of quantum devices, discover new quantum experimental setups and protocols, and improve aspects of quantum computing, communication, and simulation. The article also highlights the challenges and future possibilities in the field and provides speculative visions for the next decade.
Article
Materials Science, Multidisciplinary
Tirth Shah, Florian Marquardt, Vittorio Peano
Summary: The valley Hall effect is a useful method for creating stable waveguides for bosonic excitations such as photons and phonons. The absence of backscattering in many experiments is due to a smooth-envelope approximation that neglects large momentum transfer, but this accuracy is limited to small bulk band gaps and/or smooth domain walls. In experiments with larger bulk band gaps and hard domain walls, significant backscattering is expected. We demonstrate that in this relevant regime, the reflection of a wave at a sharp corner is highly sensitive to the orientation of the outgoing waveguide in relation to the underlying lattice. Enhanced backscattering occurs due to resonant tunneling transitions in quasimomentum space. Tracking the resonant tunneling energies with changes in waveguide orientation reveals a self-repeating fractal pattern that is also observed in the density of states and the backscattering rate at a sharp corner.
Article
Quantum Science & Technology
Riccardo Porotti, Antoine Essig, Benjamin Huard, Florian Marquardt
Summary: Quantum control has gained increasing interest recently, and feedback-based deep reinforcement learning strategies hold great promise for solving quantum control problems. This study found that reinforcement learning can successfully discover feedback strategies, achieving high-fidelity state preparation and even superposition states.
Article
Quantum Science & Technology
Naeimeh Mohseni, Thomas Foesel, Lingzhen Guo, Carlos Navarrete-Benlloch, Florian Marquardt
Summary: The study demonstrates the power of deep learning in predicting the dynamics of quantum many-body systems, even without full information during training, accurately predicting driving trajectories. This scheme provides considerable speedup for pulse optimization.
Article
Materials Science, Multidisciplinary
Lingzhen Guo, Vittorio Peano, Florian Marquardt
Summary: Recent research has discovered that atoms subjected to a time-periodic drive can form a crystal structure in phase space. The interactions between atoms lead to collective phonon excitations and phononic Chern insulator in the phase space crystal, accompanied by topologically robust chiral transport. This finding has important implications for the dynamics of two-dimensional charged particles in a strong magnetic field.
Article
Quantum Science & Technology
Piotr Sierant, Giuliano Chiriaco, Federica M. Surace, Shraddha Sharma, Xhek Turkeshi, Marcello Dalmonte, Rosario Fazio, Guido Pagano
Summary: Quantum systems undergoing unitary evolution and measurements show various non-equilibrium phase transitions, such as dissipative phase transitions in steady states and measurement-induced transitions at the level of quantum trajectories. By investigating a many-body spin system subject to periodic resetting measurements, it is found that dissipative Floquet dynamics provide a natural framework for analyzing both types of transitions. The system exhibits a dissipative phase transition between ferromagnetic and paramagnetic phases, as well as a measurement-induced transition of entanglement entropy. Analysis of multifractal properties in Hilbert space offers a common perspective on these transitions.
