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Related papers: Unitary Basis Transformations in Mixed Quantum-Cla…

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We develop circuit implementations for digital-level quantum Hamiltonian dynamics simulation algorithms suitable for implementation on a reconfigurable quantum computer, such as trapped ions. Our focus is on the co-design of a problem, its…

Quantum Physics · Physics 2020-04-09 Yunseong Nam , Dmitri Maslov

The method of differential equations has been proven to be a powerful tool for the computation of multi-loop Feynman integrals appearing in quantum field theory. It has been observed that in many instances a canonical basis can be chosen,…

High Energy Physics - Phenomenology · Physics 2017-05-23 Christoph Meyer

Any unitary transformation of quantum computational networks is explicitly decomposed, in an exact and unified form, into a sequence of a limited number of one-qubit quantum gates and the two-qubit diagonal gates that have diagonal unitary…

Quantum Physics · Physics 2007-05-23 Xijia Miao

We introduce a quantum Monte Carlo inspired reweighting scheme to accurately compute energies from optimally short quantum circuits. This effectively hybrid quantum-classical approach features both entanglement provided by a short quantum…

Quantum Physics · Physics 2019-10-07 Guglielmo Mazzola , Pauline Ollitrault , Panagiotis Barkoutsos , Ivano Tavernelli

Quantum algorithms for electronic-structure simulations are actively being developed, yet many hybrid quantum-classical approaches are bottlenecked by the measurement overhead associated with large molecular Hamiltonians. Here we introduce…

Quantum Physics · Physics 2026-03-10 Benjamin Mokhtar , Noboru Inoue , Takashi Tsuchimochi

We present a novel mixed quantum-classical approach to the coupled electron-nuclear dynamics based on the exact factorization of the electron-nuclear wave function, recently proposed in [A. Abedi, N. T. Maitra, and E. K. U. Gross, Phys.…

Chemical Physics · Physics 2015-06-18 Ali Abedi , Federica Agostini , E. K. U. Gross

The simulation of complex quantum systems on a quantum computer is studied, taking the kicked Harper model as an example. This well-studied system has a rich variety of dynamical behavior depending on parameters, displays interesting…

Quantum Physics · Physics 2007-05-23 Benjamin Levi , Bertrand Georgeot

Starting from the Schr\"odinger-equation of a composite system, we derive unified dynamics of a classical harmonic system coupled to an arbitrary quantized system. The classical subsystem is described by random phase-space coordinates…

Quantum Physics · Physics 2007-05-23 Lajos Diosi

Quantum algorithms are built enabling to find Poincar\'e recurrence times and periodic orbits of classical dynamical systems. It is shown that exponential gain compared to classical algorithms can be reached for a restricted class of…

Quantum Physics · Physics 2007-05-23 B. Georgeot

We present a quantum-classical algorithm to study the dynamics of the two-spatial-site Schwinger model on IBM's quantum computers. Using rotational symmetries, total charge, and parity, the number of qubits needed to perform computation is…

Planning energy production is a challenging task due to its cost-sensitivity, fast-moving energy markets, uncertainties in demand, and technical constraints of power plants. Thus, more complex models of this so-called \emph{unit commitment…

Quantum Physics · Physics 2024-03-07 Pascal Halffmann , Patrick Holzer , Kai Plociennik , Michael Trebing

Solving problems related to planning and operations of large-scale power systems is challenging on classical computers due to their inherent nature as mixed-integer and nonlinear problems. Quantum computing provides new avenues to approach…

Quantum Physics · Physics 2025-05-02 Willie Aboumrad , Phani R V Marthi , Suman Debnath , Martin Roetteler , Evgeny Epifanovsky

Quantum computing is emerging as a new computing resource that could be superior to conventional computing for certain classes of optimization problems. However, in principle, most existing approaches to quantum optimization are intended to…

Optimization and Control · Mathematics 2022-01-21 Chin-Yao Chang , Eric Jones , Yiyun Yao , Peter Graf , Rishabh Jain

Classical optimization is a cornerstone of the success of variational quantum algorithms, which often require determining the derivatives of the cost function relative to variational parameters. The computation of the cost function and its…

Quantum Physics · Physics 2025-07-15 Muhammad Umer , Eleftherios Mastorakis , Dimitris G. Angelakis

Path integral-based simulation methodologies play a crucial role for the investigation of nuclear quantum effects by means of computer simulations. However, these techniques are significantly more demanding than corresponding classical…

Statistical Mechanics · Physics 2018-01-17 Karsten Kreis , Kurt Kremer , Raffaello Potestio , Mark E. Tuckerman

When a quantum system interacts with an external environment, it undergoes the loss of quantum correlation (decoherence) and the loss of energy (relaxation) and eventually all of the quantum information becomes classical. Here we show a…

Quantum Physics · Physics 2007-05-23 Benjamin Recht , Yael Maguire , Seth Lloyd , I. L. Chuang , N. A. Gershenfeld

We discuss a model for quantum computing with initially mixed states. Although such a computer is known to be less powerful than a quantum computer operating with pure (entangled) states, it may efficiently solve some problems for which no…

Quantum Physics · Physics 2015-03-17 Michael Siomau , Stephan Fritzsche

Quantum computation and quantum control operate by building unitary transformations out of sequences of elementary quantum logic operations or applications of control fields. This paper puts upper bounds on the minimum time required to…

Quantum Physics · Physics 2019-01-14 Seth Lloyd , Reevu Maity

It is shown in the paper that the unitary quantum dynamics in quantum mechanics is the universal quantum driving force to speed up a quantum computation. This assertion supports strongly in theory that the unitary quantum dynamics is the…

Quantum Physics · Physics 2011-11-23 Xijia Miao

Variational algorithms have particular relevance for near-term quantum computers but require non-trivial parameter optimisations. Here we propose Analytic Descent: Given that the energy landscape must have a certain simple form in the local…

Quantum Physics · Physics 2022-05-16 Bálint Koczor , Simon C. Benjamin