Hardware Archives - IEEE Transactions on Quantum Engineering

Design and Analysis of Digital Communication Within an SoC-Based Control System for Trapped-Ion Quantum Computing

March 31, 2023Nafis IrtijaEnabling TechnologiesControl systems, Hardware, Logic gates, Quantum computing, Qubit, Radio frequency, Throughput

Large-scale quantum information processing requires the use of quantum error-correcting codes to mitigate the effects of noise in quantum devices. Topological error-correcting codes, such as surface codes, are promising candidates, as they can be implemented using only local interactions in a 2-D array of physical qubits. Procedures, such as defect braiding and lattice surgery, can […]

Variational Quantum Optimization of Nonlocality in Noisy Quantum Networks

March 31, 2023Brian DoolittleQuantum Networking & CommunicationsHardware, Integrated circuit modeling, Noise measurement, Optimization, Quantum entanglement, Quantum networks, Qubit

The noise and complexity inherent to quantum communication networks leads to technical challenges in designing quantum network protocols using classical methods. We address this issue with a hybrid variational quantum optimization (VQO) framework that simulates quantum networks on quantum hardware and optimizes the simulation using differential programming. We maximize nonlocality in noisy quantum networks to […]

Layer VQE: A Variational Approach for Combinatorial Optimization on Noisy Quantum Computers

November 2, 2022Xiaoyuan LiuOpen Access, Quantum ComputingApproximation algorithms, Hardware, Logic gates, Noise measurement, Optimization, Quantum computing, Qubit

Combinatorial optimization on near-term quantum devices is a promising path to demonstrating quantum advantage. However, the capabilities of these devices are constrained by high noise or error rates. In this article, inspired by the variational quantum eigensolver (VQE), we propose an iterative layer VQE (L-VQE) approach. We present a large-scale numerical study, simulating circuits with […]

Neural-Network Decoders for Quantum Error Correction Using Surface Codes: A Space Exploration of the Hardware Cost-Performance Tradeoffs

November 2, 2022Ramon W. J. OverwaterOpen Access, Quantum ComputingArtificial neural networks, Codes, Decoding, Hardware, Logic gates, Quantum computing, Qubit

Quantum error correction (QEC) is required in quantum computers to mitigate the effect of errors on physical qubits. When adopting a QEC scheme based on surface codes, error decoding is the most computationally expensive task in the classical electronic back-end. Decoders employing neural networks (NN) are well-suited for this task but their hardware implementation has […]

Practical Quantum K-Means Clustering: Performance Analysis and Applications in Energy Grid Classification

November 2, 2022Stephen DiAdamoOpen Access, Quantum ComputingBenchmark testing, Clustering algorithms, Computers, Estimation, Hardware, Measurement, Quantum computing

In this work, we aim to solve a practical use-case of unsupervised clustering that has applications in predictive maintenance in the energy operations sector using quantum computers. Using only cloud access to quantum computers, we complete thorough performance analysis of what some current quantum computing systems are capable of for practical applications involving nontrivial mid-to-high-dimensional […]

Effects of Dynamical Decoupling and Pulse-Level Optimizations on IBM Quantum Computers

November 2, 2022Siyuan NiuOpen Access, Quantum ComputingCalibration, Computers, Hardware, Logic gates, Performance evaluation, Quantum computing, Qubit

Currently available quantum computers are prone to errors. Circuit optimization and error mitigation methods are needed to design quantum circuits to achieve better fidelity when executed on NISQ hardware. Dynamical decoupling (DD) is generally used to suppress the decoherence error, and different DD strategies have been proposed. Moreover, the circuit fidelity can be improved by […]

QubiC: An Open-Source FPGA-Based Control and Measurement System for Superconducting Quantum Information Processors

September 29, 2021Yilun Xu; Gang Huang; Jan Balewski; Ravi Naik; Alexis Morvan; Bradley Mitchell; Kasra Nowrouzi; David I. Santiago; Irfan SiddiqiOpen Access, Quantum Computer Architecture, Quantum InformationField programmable gate arrays, Hardware, Prototypes, Quantum computing, Qubit

As quantum information processors grow in quantum bit (qubit) count and functionality, the control and measurement system becomes a limiting factor to large-scale extensibility. To tackle this challenge and keep pace with rapidly evolving classical control requirements, full control stack access is essential to system-level optimization. We design a modular field-programmable gate array (FPGA)-based system […]

Performance of Domain-Wall Encoding for Quantum Annealing

July 14, 2021Jie Chen; Tobias Stollenwerk; Nicholas ChancellorOpen Access, Quantum Computer Architecture, Quantum InformationAnnealing, Encoding, Hardware, Measurement, Optimization, Qubit, Space exploration

In this article, we experimentally test the performance of the recently proposed domain-wall encoding of discrete variables Chancellor, 2019, on Ising model flux qubit quantum annealers. We compare this encoding with the traditional one-hot methods and find that they outperform the one-hot encoding for three different problems at different sizes of both the problem and […]

Reducing the Depth of Linear Reversible Quantum Circuits

July 7, 2021Timothée Goubault de Brugière; Marc Baboulin; Benoît Valiron; Simon Martiel; Cyril AlloucheOpen Access, Quantum Computer Architecture, Quantum InformationApproximation algorithms, Hardware, Logic gates, Quantum circuit, Quantum computing, Qubit, Upper bound

In quantum computing the decoherence time of the qubits determines the computation time available, and this time is very limited when using current hardware. In this article, we minimize the execution time (the depth) for a class of circuits referred to as linear reversible circuits, which has many applications in quantum computing (e.g., stabilizer circuits, […]

Single-Qubit Fidelity Assessment of Quantum Annealing Hardware

June 25, 2021Jon Nelson; Marc Vuffray; Andrey Y. Lokhov; Carleton CoffrinOpen Access, Quantum Computer Architecture, Quantum InformationAnnealing, Hardware, Performance evaluation, Protocols, Quantum computing, Qubit, Standards

As a wide variety of quantum computing platforms become available, methods for assessing and comparing the performance of these devices are of increasing interest and importance. Inspired by the success of single-qubit error rate computations for tracking the progress of gate-based quantum computers, this work proposes a quantum annealing single-qubit assessment (QASA) protocol for quantifying […]