Materials challenges and opportunities for quantum computing hardware

Science, Journal Year: 2021, Volume and Issue: 372(6539)

Published: April 15, 2021

Quantum computing hardware technologies have advanced during the past two decades, with goal of building systems that can solve problems are intractable on classical computers. The ability to realize large-scale depends major advances in materials science, engineering, and new fabrication techniques. We identify key challenges currently limit progress five quantum platforms, propose how tackle these problems, discuss some areas for exploration. Addressing will require scientists engineers work together create new, interdisciplinary approaches beyond current boundaries field.

Language: Английский

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Quantum logic with spin qubits crossing the surface code threshold

Nature, Journal Year: 2022, Volume and Issue: 601(7893), P. 343 - 347

Published: Jan. 19, 2022

High-fidelity control of quantum bits is paramount for the reliable execution algorithms and achieving fault-tolerance, ability to correct errors faster than they occur. The central requirement fault-tolerance expressed in terms an error threshold. Whereas actual threshold depends on many details, a common target ~1% well-known surface code. Reaching two-qubit gate fidelities above 99% has been long-standing major goal semiconductor spin qubits. These qubits are well positioned scaling as can leverage advanced technology. Here we report spin-based processor silicon with single- all 99.5%, extracted from set tomography. average single-qubit remain when including crosstalk idling neighboring qubit. Utilizing this high-fidelity set, execute demanding task calculating molecular ground state energies using variational eigensolver algorithm. Now that barrier fidelity surpassed, have gained credibility leading platform, not only but also control.

Language: Английский

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Generalized Unitary Coupled Cluster Wave functions for Quantum Computation

Journal of Chemical Theory and Computation, Journal Year: 2018, Volume and Issue: 15(1), P. 311 - 324

Published: Nov. 28, 2018

We introduce a unitary coupled-cluster (UCC) ansatz termed k-UpCCGSD that is based on family of sparse generalized doubles operators, which provides an affordable and systematically improvable wave function suitable for implementation near-term quantum computer. employs k products the exponential pair double excitation operators (pCCD), together with single operators. compare its performance in both efficiency accuracy UCC employing full (UCCGSD), as well standard only excitations (UCCSD). found to show best scaling computing applications, requiring circuit depth [Formula: see text], compared text] UCCGSD, UCCSD, where N number spin orbitals η electrons. analyzed these three ansätze by making classical benchmark calculations ground state first excited H4 (STO-3G, 6-31G), H2O (STO-3G), N2 additional comparisons conventional coupled cluster methods. The results states offers good trade-off between cost, achieving chemical lower cost computers than UCCGSD UCCSD. also be more accurate UCCSD but at greater implementation. Excited are calculated orthogonally constrained variational eigensolver approach. This seen generally yield less energies corresponding states. demonstrate using specialized multideterminantal reference constructed from linear response allows energetics improved.

Language: Английский

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Computational molecular spectroscopy

Nature Reviews Methods Primers, Journal Year: 2021, Volume and Issue: 1(1)

Published: May 27, 2021

Language: Английский

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Variational Quantum Simulation of General Processes

Physical Review Letters, Journal Year: 2020, Volume and Issue: 125(1)

Published: June 29, 2020

Variational quantum algorithms have been proposed to solve static and dynamic problems of closed many-body systems. Here we investigate variational simulation three general types tasks---generalised time evolution with a non-Hermitian Hamiltonian, linear algebra problems, open system dynamics. The algorithm for generalised provides unified framework simulation. In particular, show its application in solving systems equations matrix-vector multiplications by converting these algebraic into evolution. Meanwhile, assuming tensor product structure the matrices, also propose another approach two tasks combining real imaginary Finally, introduce We variationally implement stochastic Schr\"odinger equation, which consists dissipative jump processes. numerically test six-qubit 2D transverse field Ising model under dissipation.

Language: Английский

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Quantum computational advantage via 60-qubit 24-cycle random circuit sampling

Science Bulletin, Journal Year: 2021, Volume and Issue: 67(3), P. 240 - 245

Published: Oct. 25, 2021

Language: Английский

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The prospects of quantum computing in computational molecular biology

Wiley Interdisciplinary Reviews Computational Molecular Science, Journal Year: 2020, Volume and Issue: 11(1)

Published: May 22, 2020

Quantum computers can in principle solve certain problems exponentially more quickly than their classical counterparts. We have not yet reached the advent of useful quantum computation, but when we do, it will affect nearly all scientific disciplines. In this review, examine how current algorithms could revolutionize computational biology and bioinformatics. There are potential benefits across entire field, from ability to process vast amounts information run machine learning far efficiently, for simulation that poised improve calculations drug discovery, optimization may advance fields protein structure prediction network analysis. However, these exciting prospects susceptible "hype", is also important recognize caveats challenges new technology. Our aim introduce promise limitations emerging computing technologies areas molecular

Language: Английский

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Error mitigation with Clifford quantum-circuit data

Quantum, Journal Year: 2021, Volume and Issue: 5, P. 592 - 592

Published: Nov. 26, 2021

Achieving near-term quantum advantage will require accurate estimation of observables despite significant hardware noise. For this purpose, we propose a novel, scalable error-mitigation method that applies to gate-based computers. The generates training data $\{X_i^{\text{noisy}},X_i^{\text{exact}}\}$ via circuits composed largely Clifford gates, which can be efficiently simulated classically, where $X_i^{\text{noisy}}$ and $X_i^{\text{exact}}$ are noisy noiseless respectively. Fitting linear ansatz then allows for the prediction noise-free arbitrary circuits. We analyze performance our versus number qubits, circuit depth, non-Clifford gates. obtain an order-of-magnitude error reduction ground-state energy problem on 16 qubits in IBMQ computer 64-qubit simulator.

Language: Английский

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Quantum Simulation for High-Energy Physics

PRX Quantum, Journal Year: 2023, Volume and Issue: 4(2)

Published: May 3, 2023

It is for the first time that quantum simulation high-energy physics (HEP) studied in U.S. decadal particle-physics community planning, and fact until recently, this was not considered a mainstream topic community. This speaks of remarkable rate growth subfield over past few years, stimulated by impressive advancements information sciences (QIS) associated technologies decade, significant investment area government private sectors other countries. High-energy physicists have quickly identified problems importance to our understanding nature at most fundamental level, from tiniest distances cosmological extents, are intractable with classical computers but may benefit advantage. They initiated, continue carry out, vigorous program theory, algorithm, hardware co-design simulations relevance HEP mission. Roadmap an attempt bring exciting yet challenging research spotlight, elaborate on what promises, requirements, challenges, potential solutions next decade beyond.Received 26 July 2022Revised 18 January 2023Accepted 6 March 2023DOI:https://doi.org/10.1103/PRXQuantum.4.027001Published American Physical Society under terms Creative Commons Attribution 4.0 International license. Further distribution work must maintain attribution author(s) published article's title, journal citation, DOI.Published SocietyPhysics Subject Headings (PhySH)Research AreasQuantum simulationParticles & FieldsQuantum Information, Science Technology

Language: Английский

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Learning-Based Quantum Error Mitigation

PRX Quantum, Journal Year: 2021, Volume and Issue: 2(4)

Published: Nov. 10, 2021

If NISQ-era quantum computers are to perform useful tasks, they will need employ powerful error mitigation techniques. Quasi-probability methods can permit perfect compensation at the cost of additional circuit executions, provided that nature model is fully understood and sufficiently local both spatially temporally. Unfortunately these conditions challenging satisfy. Here we present a method by which proper strategy instead be learned ab initio. Our training process uses multiple variants primary where all non-Clifford gates substituted with efficient simulate classically. The yields configuration near-optimal versus noise in real system its gate set. Having presented range learning strategies, demonstrate power technique hardware (IBM devices) exactly-emulated imperfect computers. systems suffer severities types, including temporally correlated variants. In cases protocol successfully adapts mitigates it high degree.

Language: Английский

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