English
Related papers

Related papers: The Localized Active Space Method with Unitary Sel…

200 papers

We consider the rank-reduced coupled-cluster theory with single and double excitations (RR-CCSD) introduced recently [Parrish \emph{et al.}, J. Chem. Phys. {\bf 150}, 164118 (2019)]. The main feature of this method is the decomposed form of…

Chemical Physics · Physics 2022-02-21 Michał Lesiuk

Molecular ground-state simulation is one of the most promising fields for demonstrating practical quantum advantage on near-term quantum computers. However, the Variational Quantum Eigensolver (VQE), a leading algorithm for this task, still…

Quantum Physics · Physics 2025-07-08 Runhong He , Qiaozhen Chai , Xin Hong , Ji Guan , Guolong Cui , Shengbin Wang , Shenggang Ying

Quantum computing presents a promising avenue for solving complex problems, particularly in quantum chemistry, where it could accelerate the computation of molecular properties and excited states. This work focuses on hybrid…

In this work, we have developed a multiscale computational algorithm to couple finite element method with an open source molecular dynamics code --- the Large scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) --- to perform…

Soft Condensed Matter · Physics 2019-09-17 Takahiro Murashima , Shingo Urata , Shaofan Li

The randomized linear combination of unitaries (LCU) method with many applications to early fault-tolerant quantum computing algorithms has been proposed. This quantum algorithm computes the same expectation values as the original, fully…

Quantum Physics · Physics 2026-02-16 Kaito Wada , Hiroyuki Harada , Yasunari Suzuki , Yuuki Tokunaga , Naoki Yamamoto , Suguru Endo

We consider dynamically constrained Monte-Carlo dynamics and show that this leads to the generation of long ranged effective interactions. This allows us to construct a local algorithm for the simulation of charged systems without ever…

Statistical Mechanics · Physics 2009-11-10 L. Levrel , F. Alet , J. Rottler , A. C. Maggs

An implementation of the coupled-cluster single- and double excitations (CCSD) method on two-dimensional quantum dots is presented. Advantages and limitations are studied through comparison with other high accuracy approaches for two to…

Mesoscale and Nanoscale Physics · Physics 2013-05-30 Erik Waltersson , Eva Lindroth

An iterative version of the qubit coupled cluster (QCC) method [I.G. Ryabinkin et al., J. Chem. Theory Comput. 14, 6317 (2019)] is proposed. The new method seeks to find ground electronic energies of molecules on noisy intermediate-scale…

Quantum Physics · Physics 2019-10-28 Ilya G. Ryabinkin , Robert A. Lang , Scott N. Genin , Artur F. Izmaylov

Solving electronic structure problems is considered one of the most promising applications of quantum computing. However, due to limitations imposed by the coherence time of qubits in the Noisy Intermediate Scale Quantum (NISQ) era or the…

Quantum Physics · Physics 2025-03-20 Shuo Sun , Chandan Kumar , Kevin Shen , Elvira Shishenina , Christian B. Mendl

This paper proposes a new linearized mixed data sampling (MIDAS) model and develops a framework to infer clusters in a panel regression with mixed frequency data. The linearized MIDAS estimation method is more flexible and substantially…

Econometrics · Economics 2021-02-04 Yeonwoo Rho , Yun Liu , Hie Joo Ahn

We have studied electron correlations in the doped two-dimensional (2D) Hubbard model by using the coupled-cluster method (CCM) to investigate whether or not the method can be applied to correct the independent particle approximations…

Strongly Correlated Electrons · Physics 2009-10-31 Yoshihiro Asai , Hideki Katagiri

The unified gas kinetic scheme (UGKS) is a direct modeling method based on the gas dynamical model on the mesh size and time step scales. With the implementation of particle transport and collision in a time-dependent flux function, the…

Computational Physics · Physics 2017-10-25 Yajun Zhu , Chengwen Zhong , Kun Xu

We present the time-dependent complete-active-space self-consistent-field (TD-CASSCF) method to simulate multielectron dynamics in ultrafast intense laser fields from the first principles. While based on multiconfiguration expansion, it…

Atomic Physics · Physics 2018-04-24 Takeshi Sato , Yuki Orimo , Takuma Teramura , Oyunbileg Tugs , Kenichi L. Ishikawa

In high dimensional regression, feature clustering by their effects on outcomes is often as important as feature selection. For that purpose, clustered Lasso and octagonal shrinkage and clustering algorithm for regression (OSCAR) are used…

Machine Learning · Statistics 2020-06-17 Atsumori Takahashi , Shunichi Nomura

This paper proposes a hybrid quantum-classical algorithm to solve a fundamental power system problem called unit commitment (UC). The UC problem is decomposed into a quadratic subproblem, a quadratic unconstrained binary optimization (QUBO)…

Quantum Physics · Physics 2022-04-19 Reza Mahroo , Amin Kargarian

Quantum-chemical simulations are essential for predicting energies of chemical reactions. Accurately solving the many-body Schr\"odinger equation for reagent and product states of most relevant chemical process is, however, unfeasible.…

We introduce a novel class of coupled cluster (CC) methods that leverage the seniority concept to enhance efficiency and accuracy in electronic structure calculations. While existing approaches, such as the pair coupled cluster doubles…

Coupled cluster methods are widely regarded as the gold standard of computational quantum chemistry as they are perceived to offer the best compromise between computational cost and a high-accuracy resolution of the ground state eigenvalue…

Numerical Analysis · Mathematics 2025-12-03 Muhammad Hassan , Yvon Maday

We propose a non-iterative, post hoc correction to the unitary coupled cluster theory with single, double, and triple excitations (UCCSDT) ansatz, which considers the leading-order effects of neglected quadruple excitations. We present two…

Chemical Physics · Physics 2025-08-14 Zachary W. Windom , Luke Bertels , Daniel Claudino , Rodney J. Bartlett

We describe a compilation strategy for Variational Quantum Eigensolver (VQE) algorithms which use the Unitary Coupled Cluster (UCC) ansatz, designed to reduce circuit depth and gate count. This is achieved by partitioning Pauli exponential…

Quantum Physics · Physics 2020-08-28 Alexander Cowtan , Will Simmons , Ross Duncan