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Related papers: Excited-State Downfolding Using Ground-State Forma…

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Excited state properties play a pivotal role in various chemical and physical phenomena, such as charge separation and light emission. However, the primary focus of most existing quantum algorithms has been the ground state, as seen in…

Quantum Monte Carlo methods are first-principle approaches that approximately solve the Schr\"odinger equation stochastically. As compared to traditional quantum chemistry methods, they offer important advantages such as the ability to…

Chemical Physics · Physics 2020-02-11 Jonas Feldt , Claudia Filippi

Striving to define very accurate vertical transition energies, we perform both high-level coupled cluster (CC) calculations (up to CCSDTQP) and selected configuration interaction (sCI) calculations (up to several millions of determinants)…

We show that the recently developed phaseless auxiliary-field quantum Monte Carlo (AFQMC) method can be used to study excited states, providing an alternative to standard quantum chemistry methods. The phaseless AFQMC approach, whose…

Computational Physics · Physics 2013-07-09 Wirawan Purwanto , Shiwei Zhang , Henry Krakauer

This paper presents a nonperturbative treatment of strong-coupling induced effects in atom-field systems which cannot be seen in traditional perturbative treatments invoking compromising assumptions such as the Born-Markov, rotating wave or…

Quantum Physics · Physics 2020-02-25 Jen-Tsung Hsiang , Bei-Lok Hu

Eigenvector continuation (EC) has recently attracted a lot attention in nuclear structure and reactions as a variational resummation tool for many-body expansions. While previous applications focused on ground-state energies, excited states…

Nuclear Theory · Physics 2022-06-09 Margarida Companys Franzke , Alexander Tichai , Kai Hebeler , Achim Schwenk

We report the first study using active-orbital-based and adaptive CC($P$;$Q$) approaches to describe excited electronic states. These CC($P$;$Q$) methodologies are applied, alongside their completely renormalized (CR) coupled-cluster (CC)…

Chemical Physics · Physics 2025-01-08 Karthik Gururangan , Jun Shen , Piotr Piecuch

Despite significant work on resource estimation for quantum simulation of electronic systems, the challenge of preparing states with sufficient ground state support has so far been largely neglected. In this work we investigate this issue…

We demonstrate the accuracy of ground-state energies of the transcorrelated Hamiltonian, employing sophisticated Jastrow factors obtained from variational Monte Carlo, together with the coupled cluster and distinguishable cluster methods at…

We report converged results for the ground and excited states and matter density of 16-O using realistic two-body nucleon-nucleon interactions and coupled-cluster methods and formalism developed in quantum chemistry. Most of the binding is…

Nuclear Theory · Physics 2009-11-11 M. Wloch , D. J. Dean , J. R. Gour , M. Hjorth-Jensen , K. Kowalski , T. Papenbrock , P. Piecuch

A quantum computing algorithm is proposed to obtain low-lying excited states in many-body interacting systems. The approximate eigenstates are obtained by using a quantum space diagonalization method in a subspace of states selected from…

Quantum Physics · Physics 2025-06-30 Jing Zhang , Denis Lacroix

We study the excitation spectroscopy of few-electron, parallel coupled double quantum dots (QDs). By applying a finite source drain voltage to a double QD (DQD), the first excited states observed in nonequilibrium charging diagrams can be…

Mesoscale and Nanoscale Physics · Physics 2013-07-01 T. Hatano , Y. Tokura , S. Amaha , T. Kubo , S. Teraoka , S. Tarucha

This chapter gives an introduction to qualitative and quantitative topological analyses of molecular electronic transitions. Among the possibilities for qualitatively describing how the electronic structure of a molecule is reorganized upon…

Chemical Physics · Physics 2018-11-27 Thibaud Etienne

The convergent iterative procedure for solving the groundstate Schroedinger equation is extended to derive the excitation energy and the wave function of the low-lying excited states. The method is applied to the one-dimensional quartic…

Quantum Physics · Physics 2009-11-13 R. Friedberg , T. D. Lee , W. Q. Zhao

Many-body entangled quantum states studied in condensed matter physics can be primary resources for quantum information, allowing any quantum computation to be realized using measurements alone, on the state. Such a universal state would be…

Quantum Physics · Physics 2013-05-29 Xie Chen , Bei Zeng , Zhengcheng Gu , Beni Yoshida , Isaac L. Chuang

The control and manipulation of quantum-entangled non-local states is a crucial step for the development of quantum information processing. A promising route to achieve such states on a wide scale is to couple solid-state quantum emitters…

Optics · Physics 2022-07-06 J. -B Trebbia , Q Deplano , P Tamarat , B Lounis

We propose an excited-state molecular dynamics simulation method based on variational quantum algorithms at a computational cost comparable to that of ground-state simulations. We utilize the feature that excited states can be obtained as…

Chemical Physics · Physics 2023-03-02 Hirotoshi Hirai

The preparation of quantum states using short quantum circuits is one of the most promising near-term applications of small quantum computers, especially if the circuit is short enough and the fidelity of gates high enough that it can be…

Quantum Physics · Physics 2015-10-07 D. Wecker , M. B. Hastings , M. Troyer

A systematic method for determining correlated wavefunctions of extended systems in the ground and excited states is presented. It allows to fully exploit the power of quantum-chemical programs designed for correlation calculations of…

Other Condensed Matter · Physics 2007-05-23 V. Bezugly

The structures of the ground and excited states of Be-11 were studied with a microscopic method of antisymmetrized molecular dynamics. The theoretical results reproduce the abnormal parity of the ground state and predict various kinds of…

Nuclear Theory · Physics 2009-11-07 Y. Kanada-En'yo , H. Horiuchi