24 research outputs found
Superconducting Quantum Computing: A Review
Over the last two decades, tremendous advances have been made for
constructing large-scale quantum computers. In particular, the quantum
processor architecture based on superconducting qubits has become the leading
candidate for scalable quantum computing platform, and the milestone of
demonstrating quantum supremacy was first achieved using 53 superconducting
qubits in 2019. In this work, we provide a brief review on the experimental
efforts towards building a large-scale superconducting quantum computer,
including qubit design, quantum control, readout techniques, and the
implementations of error correction and quantum algorithms. Besides the state
of the art, we finally discuss future perspectives, and which we hope will
motivate further research.Comment: Updated version, Typos corrected, New references added, New
discussions adde
Experimental quantum computational chemistry with optimised unitary coupled cluster ansatz
Simulation of quantum chemistry is one of the most promising applications of
quantum computing. While recent experimental works have demonstrated the
potential of solving electronic structures with variational quantum eigensolver
(VQE), the implementations are either restricted to nonscalable (hardware
efficient) or classically simulable (Hartree-Fock) ansatz, or limited to a few
qubits with large errors for the more accurate unitary coupled cluster (UCC)
ansatz. Here, integrating experimental and theoretical advancements of improved
operations and dedicated algorithm optimisations, we demonstrate an
implementation of VQE with UCC for H_2, LiH, F_2 from 4 to 12 qubits. Combining
error mitigation, we produce high-precision results of the ground-state energy
with error suppression by around two orders of magnitude. For the first time,
we achieve chemical accuracy for H_2 at all bond distances and LiH at small
bond distances in the experiment. Our work demonstrates a feasible path towards
a scalable solution to electronic structure calculation, validating the key
technological features and identifying future challenges for this goal.Comment: 8 pages, 4 figures in the main text, and 29 pages supplementary
materials with 16 figure
Adaptive protocol of raft in wireless network
Original distributed consensus algorithms are typically engineered with wired communication networks in mind. However, when these algorithms are applied in wireless networks, the unique characteristics of wireless communication among nodes, including high error rates, variable latency, and dynamic network topology, present novel challenges that necessitate the development of adaptive protocols. This article aims to address these challenges by designing an adaptive protocol specifically for the implementation of the Raft consensus algorithm within wireless environments. We first outline the key stages of this adaptive protocol, focusing on enhancing robustness and efficiency in the state synchronization and routing processes, which are demonstrated through extensive simulations. The proposed adaptive protocol intends to ensure consistent states across nodes in wireless networks, which promote reliable and effective distributed systems for a variety of applications in autonomous wireless networks, including Vehicle-to-everything (V2X), Internet of Things (IoT), and edge computing
Biomass Catalytic Gasification Using Rice Husk Char-supported Ni-Fe Catalysts for In-situ Tar Elimination
Influence of Surface Tension on Dynamic Characteristics of Single Bubble in Free-Field Exposed to Ultrasound
The motion of bubbles in an ultrasonic field is a fundamental physical mechanism in most applications of acoustic cavitation. In these applications, surface-active solutes, which could lower the surface tension of the liquid, are always utilized to improve efficiency by reducing the cavitation threshold. This paper examines the influence of liquids’ surface tension on single micro-bubbles motion in an ultrasonic field. A novel experimental system based on high-speed photography has been designed to investigate the temporary evolution of a single bubble in the free-field exposed to a 20.43 kHz ultrasound in liquids with different surface tensions. In addition, the R-P equations in the liquid with different surface tension are solved. It is found that the influences of the surface tension on the bubble dynamics are obvious, which reflect on the changes in the maximum size and speed of the bubble margin during bubble oscillating, as well as the weaker stability of the bubble in the liquid with low surface tension, especially for the oscillating bubble with higher speed. These effects of the surface tension on the bubble dynamics can explain the mechanism of surfactants for promoting acoustic cavitation in numerous application fields