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The kinetics of ordering and concurrent ordering and clustering is analyzed with an equation of motion initially developed to account for dissipative processes in quantum systems. A simplified energy eigenstructure, or…

Materials Science · Physics 2018-09-28 Ryo Yamada , Michael R. von Spakovsky , William T. Reynolds,

Determining ground state energies of quantum systems by hybrid classical/quantum methods has emerged as a promising candidate application for near-term quantum computational resources. Short of large-scale fault-tolerant quantum computers,…

Quantum Physics · Physics 2016-10-25 Nicholas C. Rubin

In this work, we study the time-dependent behaviour of quantum correlations of a system of an inverted oscillator governed by out-of-equilibrium dynamics using the well-known Schwinger-Keldysh formalism in presence of quantum mechanical…

High Energy Physics - Theory · Physics 2024-10-04 Sayantan Choudhury , Suman Dey , Rakshit Mandish Gharat , Saptarshi Mandal , Nilesh Pandey

We simulate the time-dependent coherent dynamics of a spatially indirect exciton (an electron-hole pair with the two particles confined in different layers) in a GaAs coupled quantum well system. We use a unitary wave-packet propagation…

Mesoscale and Nanoscale Physics · Physics 2016-05-25 Federico Grasselli , Andrea Bertoni , Guido Goldoni

We address the nonadiabatic quantum dynamics of macrosystems with several coupled electronic states, taking into account the possibility of multi-state conical intersections. The general situation of an arbitrary number of states and…

Chemical Physics · Physics 2009-11-13 Etienne Gindensperger , Lorenz S. Cederbaum

We present a derivation of the Redfield formalism for treating the dissipative dynamics of a time-dependent quantum system coupled to a classical environment. We compare such a formalism with the master equation approach where the…

We recently proposed a novel approach to converging electronic energies equivalent to high-level coupled-cluster (CC) computations by combining the deterministic CC($P$;$Q$) formalism with the stochastic configuration interaction (CI) and…

Chemical Physics · Physics 2021-03-23 J. Emiliano Deustua , Jun Shen , Piotr Piecuch

This paper proposes a data-driven version of the Benders decomposition algorithm applied to the stochastic unit commitment (SUC) problem. The proposed methodology aims at finding a trade-off between the size of the Benders master problem…

Optimization and Control · Mathematics 2019-12-04 Baudouin Vandenbussche , Stefanos Delikaraoglou , Ignacio Blanco , Gabriela Hug

The dynamical generation of entanglement in closed bipartite systems is investigated in the semiclassical regime. We consider a model of two particles, initially prepared in a product of coherent states, evolving in time according to a…

Quantum Physics · Physics 2015-05-19 A. D. Ribeiro , R. M. Angelo

We propose a new variational quantum algorithm, which we refer to as TIMES-ADAPT, that prepares time-evolved states in a low-energy or symmetric subspace of a time-independent Hamiltonian on a quantum computer. Using a specially trained…

We introduce a hybrid quantum-classical algorithm, the localized active space unitary selective coupled cluster singles and doubles (LAS-USCCSD) method. Derived from the localized active space unitary coupled cluster (LAS-UCCSD) method,…

Unitary coupled cluster (UCC) theory offers a promising Hermitian alternative to conventional coupled cluster (CC) theory, but its practical implementation is hindered by the non-truncating nature of the Baker-Campbell-Hausdorff (BCH)…

Chemical Physics · Physics 2025-05-05 Justin T. Phillips , Lauren N. Koulias , Stephen H. Yuwono , A. Eugene DePrince

Density functional theory (DFT) provides convenient electronic structure methods for the study of molecular systems and materials. Regular Kohn-Sham DFT calculations rely on unitary transformations to determine the ground-state electronic…

Chemical Physics · Physics 2022-10-10 Greta Jacobson , Juan M. Marmolejo-Tejada , Martín A. Mosquera

We develop a static quantum embedding scheme that utilizes different levels of approximations to coupled cluster (CC) theory for an active fragment region and its environment. To reduce the computational cost, we solve the local fragment…

Chemical Physics · Physics 2024-11-13 Avijit Shee , Fabian M. Faulstich , Birgitta Whaley , Lin Lin , Martin Head-Gordon

Many-body quantum dynamics defined on a spatial lattice and in discrete time -- either as stroboscopic Floquet systems or quantum circuits -- has been an active area of research for several years. Being discrete in space and time, a natural…

Quantum Physics · Physics 2024-11-04 Pieter W. Claeys , Austen Lamacraft

The single excitation subspace (SES) method for universal quantum simulation is investigated for a number of diatomic molecular collision complexes. Assuming a system of $n$ tunably-coupled, and fully-connected superconducting qubits,…

Quantum Physics · Physics 2016-02-02 P. C. Stancil , H. You , A. Cook , A. T. Sornborger , M. R. Geller

In this work we study a dissipative field theory where the dissipation process is manifestly related to dynamical entanglement and put it in the holographic context. Such endeavour is realized by further development of a canonical approach…

High Energy Physics - Theory · Physics 2018-02-12 M. Botta Cantcheff , Alexandre L. Gadelha , Dáfni F. Z. Marchioro , Daniel Luiz Nedel

The clustering of data into physically meaningful subsets often requires assumptions regarding the number, size, or shape of the subgroups. Here, we present a new method, simultaneous coherent structure coloring (sCSC), which accomplishes…

Machine Learning · Statistics 2019-11-26 Brooke E. Husic , Kristy L. Schlueter-Kuck , John O. Dabiri

We consider a composite open quantum system consisting of a fast subsystem coupled to a slow one. Using the time-scale separation, we develop an adiabatic elimination technique to derive at any order the reduced model describing the slow…

Quantum Physics · Physics 2017-07-11 Remi Azouit , Francesca Chittaro , Alain Sarlette , Pierre Rouchon

We provide several examples and an intuitive diagrammatic representation demonstrating the use of two-qubit unitary transformations for mapping coupled spin Hamiltonians to simpler ones and vice versa. The corresponding dualities may be…

Quantum Physics · Physics 2016-06-01 Gernot Schaller , Ralf Schützhold