Article
Engineering, Electrical & Electronic
Yu Dian Lim, Hong Yu Li, Peng Zhao, Jing Tao, Luca Guidoni, Chuan Seng Tan
Summary: Silicon photonics structures for optical addressing of trapped ions in quantum computing applications were developed in this study. Grating-waveguide-grating structures of various designs were fabricated, with gratings of 25 and 30 mu m radius of curvature showing lower power loss and better-focused beam profiles compared to those with 12 and 15 mu m radius of curvature. The beam width ranged between 17.31 to 41.54 mu m, allowing for optical addressing of 2 to 4 Sr+ ions trapped along the ground electrode of the ion trap.
IEEE PHOTONICS JOURNAL
(2021)
Article
Physics, Multidisciplinary
Wentao Chen, Yao Lu, Shuaining Zhang, Kuan Zhang, Guanhao Huang, Mu Qiao, Xiaolu Su, Jialiang Zhang, Jing-Ning Zhang, Leonardo Banchi, M. S. Kim, Kihwan Kim
Summary: A minimal-loss programmable phononic network is demonstrated, which can deterministically prepare and detect any phononic state. The network can be extended to reveal quantum advantage and has high reconstruction fidelities for both single- and two-phonon states.
Article
Quantum Science & Technology
F. R. Lebrun-Gallagher, N. Johnson, M. Akhtar, S. Weidt, D. Bretaud, S. J. Hile, A. Owens, F. Bonus, W. K. Hensinger
Summary: Microfabricated ion-trap devices offer a promising pathway towards scalable quantum computing. The development of large-scale ion-trap arrays and networks faces challenges in thermal management. This research presents a modular cooling system for multiple ion-trapping experiments.
QUANTUM SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Jacob Whitlow, Zhubing Jia, Ye Wang, Chao Fang, Jungsang Kim, Kenneth R. Brown
Summary: This article presents a quantum simulation of conical intersections using a trapped atomic ion system, and experimentally observes the manifestation of geometric phase, demonstrating the advantage of combining spin and motion for quantum simulation of chemical reactions.
Article
Multidisciplinary Sciences
O. P. de Sa Neto, H. A. S. Costa, G. A. Prataviera, M. C. de Oliveira
Summary: In this study, estimation theory is applied to a system consisting of two interacting trapped ions. A simple scheme is introduced using the Fisher matrix formalism to estimate the temperature of the longitudinal vibrational modes of the ions. The interaction between the ions is utilized to effectively infer the temperature of individual ions by optimizing the interaction time evolution and measuring only one of the ions. The effect of a non-thermal reservoir on the inference approach is also investigated.
SCIENTIFIC REPORTS
(2022)
Article
Optics
T. Tassis, F. L. Semiao
Summary: Trapped ions driven by electromagnetic radiation are highly developed quantum technologies, ranging from proof-of-principle experiments to on-chip integration for quantum information units. With novel trap and cavity designs, faster quantum gates and state transfers become possible. However, there is currently limited knowledge on models and applications that go beyond the weak-driving scenario.
Article
Optics
Silpa Muralidharan, Kenji Toyoda
Summary: We demonstrate the control of polaritons in the JCH model using trapped ions. By illuminating a linear ion crystal with optical beams nearly resonant to the RSB transition, polaritonic excitations can exist. Each polariton consists of one internal excitation and one vibrational quantum, and can hop between ion sites with external control. We show the blockade of polariton hopping in a two-ion system, and propose that the technique can be used for detailed studies of an artificial many-body system.
APPLIED PHYSICS B-LASERS AND OPTICS
(2023)
Article
Physics, Applied
Minjae Lee, Junho Jeong, Yunjae Park, Changhyun Jung, Taehyun Kim, Dong-il Cho
Summary: This paper introduces an ion shuttling method for a MEMS-fabricated surface ion trap, where calculated voltage sets are used to achieve successful ion transportation experiments.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2021)
Article
Physics, Applied
Mizuki Shirao, Daniel Klawson, Sara Mouradian, Ming C. Wu
Summary: A one-dimensional focusing grating coupler array based in silicon nitride (SiN) was proposed for trapped ion qubit manipulation. The design was optimized to achieve high directionality, small beam diameter, and low crosstalk. Additionally, the impact of fabrication errors on system performance was also investigated through simulation analysis.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2022)
Article
Multidisciplinary Sciences
R. Srinivas, S. C. Burd, H. M. Knaack, R. T. Sutherland, A. Kwiatkowski, S. Glancy, E. Knill, D. J. Wineland, D. Leibfried, A. C. Wilson, D. T. C. Allcock, D. H. Slichter
Summary: Researchers have successfully demonstrated high-fidelity laser-free universal control of two trapped-ion qubits by utilizing microwave technology combined with radiofrequency magnetic field gradients. This technology allows for simultaneous entangling operations on multiple pairs of ions without increasing control signal power or complexity.
Article
Optics
J. D. Arias Espinoza, M. Mazzanti, K. Fouka, R. X. Schuessler, Z. Wu, P. Corboz, R. Gerritsma, A. Safavi-Naini
Summary: The proposed method uses optical tweezers to engineer the sound-wave spectrum of trapped ion crystals, allowing for tuning of interactions and connectivity beyond current setups. Demonstrated feasibility of generating target spin-spin interaction patterns in both one- and two-dimensional crystals using realistic tweezer settings and experimentally relevant trap parameters. This approach advances quantum simulation in trapped-ion platforms by enabling realization of a broader family of quantum spin Hamiltonians.
Article
Optics
B. P. Ruzic, T. A. Barrick, J. D. Hunker, R. J. Law, B. K. McFarland, H. J. McGuinness, L. P. Parazzoli, J. D. Sterk, J. W. Van der Wall, D. Stick
Summary: In this paper, the impact of coherent motional excitation on the entangling-gate error in trapped-ion quantum computers is analyzed. The results show that a small amount of coherent displacement can erode gate performance, but this error can be suppressed by adjusting the relative phase or using Walsh modulation. Experimental data from transported ions is also used to analyze the impact of coherent displacement on gate error under realistic conditions.
Review
Computer Science, Information Systems
Stefanie Castillo
Summary: This paper focuses on the electronic control system of a trapped-ion quantum processor, which lacks a systematic electronic system-level approach for its conception, design, implementation, and/or verification. By conducting a systematic literature review, this study identifies existing literature on the topic and provides possible research directions and considerations. It lays a foundation for understanding the requirements and environment of the electronic control system and serves as a comprehensive overview of the existing body of knowledge in this field.
Article
Physics, Multidisciplinary
C. Will, M. Bohman, T. Driscoll, M. Wiesinger, F. Abbass, M. J. Borchert, J. A. Devlin, S. Erlewein, M. Fleck, B. Latacz, R. Moller, A. Mooser, D. Popper, E. Wursten, K. Blaum, Y. Matsuda, C. Ospelkaus, W. Quint, J. Walz, C. Smorra, S. Ulmer
Summary: This article focuses on the remote sympathetic cooling of a single proton with laser-cooled Be-9(+) ions. Through analytical calculations and numerical simulations, two cooling schemes capable of achieving proton temperatures of about 10 mK in short cooling times are identified. These techniques allow for improved sampling rates and reduced systematic uncertainties in precision measurements based on trapped charged particles.
NEW JOURNAL OF PHYSICS
(2022)
Article
Physics, Fluids & Plasmas
Sheng-Chen Liu, Lin Cheng, Gui-Zhong Yao, Ying-Xiang Wang, Liang-You Peng
Summary: Almost every quantum circuit in current stage relies on two-qubit gates, which are crucial for quantum computing in any platform. In trapped-ion systems, entangling gates based on Molmer-Sorensen schemes are widely used, utilizing the collective motional modes of ions and laser-controlled internal states as qubits. The key to achieving high-fidelity and robust gates is minimizing entanglement between qubits and motional modes under various sources of errors. In this work, an efficient numerical method is proposed to search for high-quality solutions for phase-modulated pulses, which solves the problem through a combination of linear algebra and quadratic equations. The method demonstrates effectiveness up to 60 ions and overcomes convergence issues, meeting the gate design needs in current trapped-ion experiments.
Article
Education, Scientific Disciplines
Abraham Asfaw, Alexandre Blais, Kenneth R. Brown, Jonathan Candelaria, Christopher Cantwell, Lincoln D. Carr, Joshua Combes, Dripto M. Debroy, John M. Donohue, Sophia E. Economou, Emily Edwards, Michael F. J. Fox, Steven M. Girvin, Alan Ho, Hilary M. Hurst, Zubin Jacob, Blake R. Johnson, Ezekiel Johnston-Halperin, Robert Joynt, Eliot Kapit, Judith Klein-Seetharaman, Martin Laforest, H. J. Lewandowski, Theresa W. Lynn, Corey Rae H. McRae, Celia Merzbacher, Spyridon Michalakis, Prineha Narang, William D. Oliver, Jens Palsberg, David P. Pappas, Michael G. Raymer, David J. Reilly, Mark Saffman, Thomas A. Searles, Jeffrey H. Shapiro, Chandralekha Singh
Summary: The paper provides a roadmap for constructing a quantum engineering education program to meet the workforce needs of the United States and international community. Through a workshop and drawing on best practices, the researchers make specific findings and recommendations, including the design of a first quantum engineering course accessible to all STEM students and the education and training methods for producing quantum-proficient engineers.
IEEE TRANSACTIONS ON EDUCATION
(2022)
Article
Chemistry, Physical
Christian Wellers, Magnus R. Schenkel, Gouri S. Giri, Kenneth R. Brown, Stephan Schiller
Summary: In this study, controlled loading, sympathetic cooling, mass spectrometric identification, and vibrational excitation of ultracold single HD+ ions trapped in a tightly confining radiofrequency trap are demonstrated for the first time using single laser-cooled Be+ ions for sympathetic cooling. The apparatus can also be utilized for preparing other single ions, both lighter and heavier than the coolant ion.
Article
Computer Science, Hardware & Architecture
Prakash Murali, Dripto M. Debroy, Kenneth R. Brown, Margaret Martonosi
Summary: Trapped ions (TIs) are a leading candidate for building Noisy Intermediate-Scale Quantum (NISQ) hardware. A modular architecture named Quantum Charge Coupled Device (QCCD) has been proposed to achieve 50-100 qubit TI devices. Extensive architectural studies have been performed to evaluate the design choices and provide recommendations for highly reliable and performant application executions. The insights from these studies have the potential to influence quantum computing hardware in the near future.
COMMUNICATIONS OF THE ACM
(2022)
Article
Physics, Applied
Bichen Zhang, Swarnadeep Majumder, Pak Hong Leung, Stephen Crain, Ye Wang, Chao Fang, Dripto M. Debroy, Jungsang Kim, Kenneth R. Brown
Summary: In this paper, a method for reducing coherent errors by using hidden inverses is demonstrated. The effectiveness of this method is numerically simulated and experimentally validated on a trapped-ion quantum computer.
PHYSICAL REVIEW APPLIED
(2022)
Article
Physics, Multidisciplinary
Zhubing Jia, Ye Wang, Bichen Zhang, Jacob Whitlow, Chao Fang, Jungsang Kim, Kenneth R. Brown
Summary: The study proposes a general method to determine Fock state distributions and reconstruct the density matrix of arbitrary multimode motional states, applicable to any system with Jaynes-Cummings-type interactions.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
Mingyu Kang, Ye Wang, Chao Fang, Bichen Zhang, Omid Khosravani, Jungsang Kim, Kenneth R. Brown
Summary: This study develops filter functions for Molmer-Sorensen gates in trapped-ion quantum computers, accurately predicting the change in gate error due to small parameter fluctuations at any frequency. Experimental results show that using these filter functions can significantly improve gate fidelity in a five-ion chain.
PHYSICAL REVIEW APPLIED
(2023)
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
Quantum Science & Technology
Mingyu Kang, Wesley C. Campbell, Kenneth R. Brown
Summary: For quantum error-correcting codes, erasures, or errors with known locations, are more favorable than Pauli errors. Convert physical noise into erasures can significantly enhance quantum error correction. In this study, we apply the concept of performing erasure conversion by encoding qubits into metastable atomic states, proposed by Wu, Kolkowitz, Puri, and Thompson in 2022, to trapped ions.
Article
Optics
Lu Qi, Evan C. Reed, Kenneth R. Brown
Summary: Control of the external degree of freedom is crucial for the applications of trapped molecular ions in spectroscopy, precision measurements, and quantum information technology. In this study, we demonstrate near ground-state cooling of axial motional modes of a calcium mono-oxide ion through sympathetic sideband cooling with a cotrapped calcium ion. We also observe that the phonon state of the axial out-of-phase mode of the ion chain remains unchanged while the mode frequency is adiabatically ramped up and/or down, which is essential for investigating the proposed molecular dipole-phonon interaction.
Article
Quantum Science & Technology
Theerapat Tansuwannont, Balint Pato, Kenneth R. Brown
Summary: The Shor fault-tolerant error correction (FTEC) scheme uses transversal gates and ancilla qubits in the cat state to prevent error propagation. An adaptive syndrome measurement technique is introduced to improve the scheme. Simulations show that the proposed protocols can maintain code distance, increase pseudothreshold, and reduce the average number of measurement rounds compared to the traditional Shor scheme.
Article
Optics
Zhubing Jia, Shilin Huang, Mingyu Kang, Ke Sun, Robert F. Spivey, Jungsang Kim, Kenneth R. Brown
Summary: In trapped-ion quantum computers, spin-dependent force and phonons are used to generate two-qubit entangling gates. To maintain high fidelity under fluctuating experimental parameters, robust pulse-design methods are used. An improved method is proposed that guarantees the robustness of the rotation angle against uniform mode-frequency drifts. Experimental results show significantly improved robustness and gate fidelity compared to a single frequency-modulated pulse.
Proceedings Paper
Computer Science, Theory & Methods
Aniket S. Dalvi, Filip Mazurek, Leon Riesebos, Jacob Whitlow, Swarnadeep Majumder, Kenneth R. Brown
Summary: Duke ARTIQ Extensions (DAX) provides a framework for modular control software in ion-trap quantum systems, while DAX.program-sim (DPS) framework allows for simulation of quantum programs at the level of quantum operations. This simulation addition is essential for testing and benchmarking quantum hardware. The DPS pipeline has the same input as the hardware, enabling flexible simulation options.
2022 IEEE INTERNATIONAL CONFERENCE ON QUANTUM COMPUTING AND ENGINEERING (QCE 2022)
(2022)
Proceedings Paper
Computer Science, Theory & Methods
Leon Riesebos, Kenneth R. Brown
Summary: Modern quantum computers heavily rely on real-time control systems for operation. However, testing real-time control software is often complex, and existing simulation software is not practical for software testing. To address this issue, we developed an interactive simulator that can simulate signals at the application programming interface level. Our simulation infrastructure achieves an average 6.9 times faster simulation speed compared to hardware execution, with an average accuracy of 97.9% in simulating the position of the timeline cursor when the appropriate configuration is chosen.
2022 IEEE INTERNATIONAL CONFERENCE ON QUANTUM COMPUTING AND ENGINEERING (QCE 2022)
(2022)
Proceedings Paper
Computer Science, Theory & Methods
Leon Riesebos, Brad Bondurant, Jacob Whitlow, Junki Kim, Mark Kuzyk, Tianyi Chen, Samuel Phiri, Ye Wang, Chao Fang, Andrew Van Horn, Jungsang Kim, Kenneth R. Brown
Summary: Real-time control software and hardware are crucial for operating quantum computers. This study proposes a systematic design strategy for modular real-time quantum control software, which can significantly reduce the execution time overhead of kernels without increasing the binary size. The experiment demonstrates the modularity and portability of the software architecture on two different ion-trap quantum systems.
2022 IEEE INTERNATIONAL CONFERENCE ON QUANTUM COMPUTING AND ENGINEERING (QCE 2022)
(2022)
Article
Optics
Joel Rajakumar, Jai Moondra, Bryan Gard, Swati Gupta, Creston D. Herold
Summary: In this study, methods for constructing any target coupling graph using limited global controls in an Ising-like quantum spin system are presented. The results of numerical experiments and noise simulations demonstrate the superiority of this approach.
