Article
Physics, Applied
Jeroen Danon, Anasua Chatterjee, Andras Gyenis, Ferdinand Kuemmeth
Summary: The implementation of large-scale fault-tolerant quantum computers requires integrating millions of physical qubits with low error rates and protecting them from environmental noise. Protective approaches include encoding qubits in global or local decoherence-free subspaces, and in dynamical sweet spots of driven systems.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Multidisciplinary
Tim Menke, William P. Banner, Thomas R. Bergamaschi, Agustin Di Paolo, Antti Vepsalainen, Steven J. Weber, Roni Winik, Alexander Melville, Bethany M. Niedzielski, Danna Rosenberg, Kyle Serniak, Mollie E. Schwartz, Jonilyn L. Yoder, Alan Aspuru-Guzik, Simon Gustavsson, Jeffrey A. Grover, Cyrus F. Hirjibehedin, Andrew J. Kerman, William D. Oliver
Summary: This study presents a superconducting circuit architecture that enables two-local and three-local interactions between three flux qubits through a designed coupling module. The system Hamiltonian is estimated using multiqubit pulse sequences implementing Ramsey-type interferometry. The three-local interaction can be coherently tuned over several MHz via the coupler flux biases and can also be turned off. This research has significant applications in quantum annealing, analog quantum simulation, and gate-model quantum computation.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Philip D. Gregory, Jacob A. Blackmore, Sarah L. Bromley, Jeremy M. Hutson, Simon L. Cornish
Summary: Quantum states with long-lived coherence are crucial for quantum computation, simulation, and metrology. By characterizing and eliminating the dominant mechanisms of decoherence in ultracold molecular qubits, we achieved coherence times exceeding 5.6 seconds.
Article
Physics, Multidisciplinary
Yi-Hao Kang, Yang Xiao, Zhi-Cheng Shi, Yu Wang, Jian-Qun Yang, Jie Song, Yan Xia
Summary: We propose an effective protocol for implementing nonadiabatic geometric quantum gates of cat-state qubits in Kerr-nonlinear resonators driven by two-photon squeezing drives. By coupling the Kerr-nonlinear resonators with an auxiliary qutrit with proper coupling strengths, the selective transition of the auxiliary qutrit is achieved. This selective transition can be utilized in implementing a set of useful quantum gates, including phase gates, NOT gates, controlled-phase gates, controlled NOT gates, and Toffoli gates. Numerical simulations demonstrate the robustness of the gate implementations against systematic errors, random noise, and decoherence. Thus, the protocol may contribute to robust and scalable quantum computation based on cat-state qubits.
NEW JOURNAL OF PHYSICS
(2023)
Article
Physics, Multidisciplinary
Craig R. Clark, Holly N. Tinkey, Brian C. Sawyer, Adam M. Meier, Karl A. Burkhardt, Christopher M. Seck, Christopher M. Shappert, Nicholas D. Guise, Curtis E. Volin, Spencer D. Fallek, Harley T. Hayden, Wade G. Rellergert, Kenton R. Brown
Summary: This paper introduces a new variant of the light-shift scheme for entanglement generation in trapped-ion systems, and demonstrates its efficiency and stability through experimental validation, achieving a Bell state in 35 μs with high fidelity. The use of a 532 nm gate laser wavelength effectively suppresses intrinsic photon scattering errors to approximately 1 x 10(-5).
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Marcin M. Wysokinski, Marcin Plodzien, Mircea Trif
Summary: The study demonstrates the potential of electrically driven hole spins for fast manipulation, detection, and long-range entanglement in the absence of external magnetic field, with higher robustness against external noises. These results suggest that hole spins are favorable qubits for scalable quantum computing by purely electrical means.
Review
Nanoscience & Nanotechnology
Irfan Siddiqi
Summary: The review explores the major sources of decoherence in superconducting qubits and the trade-offs between simple and complex circuit designs. It also discusses the impact of materials optimization strategies on quantum computing.
NATURE REVIEWS MATERIALS
(2021)
Article
Physics, Multidisciplinary
Tony J. G. Apollaro, Salvatore Lorenzo, Francesco Plastina, Mirko Consiglio, Karol Zyczkowski
Summary: The transfer of quantum information between different locations is crucial for many quantum information processing tasks. While the transfer of a single qubit state has been extensively studied, the transfer of a many-body system configuration has remained a challenge. This paper addresses the problem of transferring the state of n interacting qubits and derives a general expression for the fidelity of an arbitrary quantum state transfer protocol. By adopting a weak-coupling scheme in a spin chain, the conditions for high-fidelity transfer of three and four interacting qubits are obtained.
NEW JOURNAL OF PHYSICS
(2022)
Article
Chemistry, Physical
Yu Cheng, Jun Shu, Lin Xu, Yangyang Xia, Lulu Du, Gang Zhang, Liqiang Mai
Summary: By utilizing a gradient nanowire cathode, the interface contact issues in SSLBs can be improved, enhancing the efficiency of ion and electron transport to enhance the structural stability and electrochemical performance of solid-state lithium batteries.
ADVANCED ENERGY MATERIALS
(2021)
Article
Optics
Jeremie Guillaud, Mazyar Mirrahimi
Summary: This study estimates and analyzes the error rates and resource overheads of using the repetition cat qubit approach for universal and fault-tolerant quantum computation. By performing Monte Carlo simulations, it is shown that very low logical error rates can be achieved with reasonable resource overheads and parameters within the reach of near-term circuit QED experiments.
Article
Physics, Applied
Nikos Iliopoulos, Ioannis Thanopulos, Vasilios Karanikolas, Emmanuel Paspalakis
Summary: We investigate the entanglement dynamics between two qubits and a graphene nanodisk using the macroscopic quantum electrodynamics method. Our findings show that as the free-space decay rate increases, the decaying Rabi oscillations in the qubit population dynamics change to complex non-Markovian dynamical population evolution. This is also reflected in the concurrence, which can reach values up to 0.5 under weak or moderate light-matter coupling conditions and transiently higher values under stronger coupling conditions. These results demonstrate the potential of graphene nanostructures for realizing high degrees of entanglement at the nanoscale, which is crucial for quantum technology applications.
APPLIED PHYSICS LETTERS
(2022)
Review
Quantum Science & Technology
Zhen Yang, Ming-Qiang Bai, Zhi-Wen Mo
Summary: This research proposes two models to reduce the quantum cost of the client in blind quantum computation, by making full use of the server's quantum ability and measurement-based quantum computation, as well as replacing some units to ensure the computation process remains blind to the server.
QUANTUM INFORMATION PROCESSING
(2022)
Article
Chemistry, Multidisciplinary
Guanjie Lu, Wei Liu, Zuguang Yang, Yumei Wang, Weikang Zheng, Rongrui Deng, Ronghua Wang, Li Lu, Chaohe Xu
Summary: A superlithiophilic, moisture-resistant, and robust interlayer is demonstrated by in situ forming an AlF3 interlayer on the LLZTO surface, overcoming the instability, poor interfacial contact, and dendrite issue of LLZTO in all-solid-state lithium batteries. The AlF3-modified LLZTO offers a significantly reduced interfacial resistance, achieves a critical current density of 1.2 mA cm(-2) and long-term stability of over 4000-4700 h, and exhibits regulated Li plating/stripping behaviors.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Vitaly Sukharenko, Roger Dorsinville
Summary: In this study, we compared reconstructed quantum state images of a birefringent sample using direct quantum state tomography and inverse numerical optimization technique. By characterizing the birefringence in a transparent plastic sample with polarization sensitive measurement, we reconstructed the density matrix, degree of entanglement, and concurrence for each pixel of the sample. The experimental results highlight noise reduction, image enhancement, and improved density matrix estimation. The technique described in this work has various potential applications.
APPLIED SCIENCES-BASEL
(2022)
Article
Chemistry, Physical
Fanglin Wu, Zhen Chen, Shan Fang, Wenhua Zuo, Guk-Tae Kim, Stefano Passerini
Summary: Interfacial issues hinder the progress of current solid-state battery technology, and interface engineering approaches are needed to achieve solid-state configuration. Ionic liquids, which are viscous and nonflammable, can optimize the interface between solid electrodes and solid electrolytes, accelerate ion transport at the interface, and create engineered interphases using robust chemical building blocks. This review summarizes the roles of ionic liquids in solid-state batteries, with a focus on the interface, and highlights their functionality and applicability in next-generation battery systems.
ENERGY STORAGE MATERIALS
(2023)