English
Related papers

Related papers: A Stochastic Approach to Unitary Coupled Cluster

200 papers

We present a new method for state preparation using the Unitary Vibrational Coupled-Cluster (UVCC) technique. Our approach utilizes redundancies in the Hilbert space in the direct mapping of vibrational modes into qubits. By eliminating…

Quantum Physics · Physics 2024-12-06 Michal Szczepanik , Emil Zak

Near-term quantum devices require wavefunction ans\"atze that are expressive while also of shallow circuit depth in order to both accurately and efficiently simulate molecular electronic structure. While unitary coupled cluster (e.g.,…

Unit Commitment (UC) is a core optimization problem in power system operation and electricity market scheduling. It determines the optimal on/off status and dispatch of generating units while satisfying system, operational, and market…

Quantum Physics · Physics 2026-01-06 Milad Hasanzadeh , Ali Rajabi , Amin Kargarian

We present a new hybrid quantum-classical algorithm for optimizing unitary coupled-cluster (UCC) wave functions deemed the projective quantum eigensolver (PQE), amenable to near-term noisy quantum hardware. Contrary to variational quantum…

Quantum Physics · Physics 2021-08-10 Nicholas H. Stair , Francesco A. Evangelista

Fault-tolerant quantum computation (FTQC) is essential to implement quantum algorithms in a noise-resilient way, and thus to enjoy advantages of quantum computers even with presence of noise. In FTQC, a quantum circuit is decomposed into…

Quantum Physics · Physics 2025-07-23 Kohdai Kuroiwa , Yuya O. Nakagawa

A formal analysis is conducted on the exactness of various forms of unitary coupled cluster (UCC) theory based on particle-hole excitation and de-excitation operators. Both the conventional single exponential UCC parameterization and a…

Chemical Physics · Physics 2020-01-29 Francesco A. Evangelista , Garnet Kin-Lic Chan , Gustavo E. Scuseria

This paper introduces the first quantum computing framework for Stochastic Quantum Power Flow (SQPF) analysis in power systems. The proposed method leverages quantum states to encode power flow distributions, enabling the use of Quantum…

Quantum Physics · Physics 2025-01-13 Brynjar Sævarsson , Hjörtur Jóhannsson , Spyros Chatzivasileiadis

We present a quantum linear response (qLR) approach within an active-space framework for computing indirect nuclear spin-spin coupling constants, a key ingredient in NMR spectra predictions. The method employs the unitary coupled cluster…

In this study, we employ the variational quantum eigensolver algorithm with a multireference unitary coupled cluster ansatz to report the ground state energy of the BeH2 molecule in a geometry where strong correlation effects are…

Sampling from complicated probability distributions is a hard computational problem arising in many fields, including statistical physics, optimization, and machine learning. Quantum computers have recently been used to sample from…

We propose a streamlined combination scheme of the transcorrelation (TC) and coupled cluster (CC) theory, which not only increases the convergence rate with respect to the basis set, but also extends the applicability of the lowest order CC…

Strongly Correlated Electrons · Physics 2021-07-28 Ke Liao , Thomas Schraivogel , Hongjun Luo , Daniel Kats , Ali Alavi

A dynamical formulation of coupled cluster theory is derived using a variational principle. By allowing time-dependent single-particle functions, a high degree of adaptivity is introduced, allowing complex systems to be simulated with high…

Quantum Physics · Physics 2014-11-25 Simen Kvaal

In this work, we develop a size extensive Auxiliary-Field Quantum Monte Carlo (AFQMC) approach that scales as $O(N^5)$ for local energy evaluation by treating the Coupled Cluster Singles and Doubles (CCSD) trial wavefunctions…

Chemical Physics · Physics 2026-05-13 Yichi Zhang , Ankit Mahajan , Yann Damour , Sandeep Sharma

We describe further details of the Stochastic Coupled Cluster method and a diagnostic of such calculations, the shoulder height, akin to the plateau found in Full Configuration Interaction Quantum Monte Carlo. We describe an initiator…

Chemical Physics · Physics 2016-03-23 James S. Spencer , Alex J. W. Thom

In quantum chemistry, the variational quantum eigensolver (VQE) is a promising algorithm for molecular simulations on near-term quantum computers. However, VQEs using hardware-efficient circuits face scaling challenges due to the barren…

Quantum Physics · Physics 2024-09-27 Rui Mao , Guojing Tian , Xiaoming Sun

Applications of quantum simulation algorithms to obtain electronic energies of molecules on noisy intermediate-scale quantum (NISQ) devices require careful consideration of resources describing the complex electron correlation effects. In…

Quantum Physics · Physics 2020-04-17 Mekena Metcalf , Nicholas P. Bauman , Karol Kowalski , Wibe A. de Jong

In single-reference coupled-cluster (CC) methods, one has to solve a set of non-linear polynomial equations in order to determine the so-called amplitudes which are then used to compute the energy and other properties. Although it is of…

Chemical Physics · Physics 2021-09-10 Antoine Marie , Fábris Kossoski , Pierre-François Loos

Continuous-variable cluster states offer a potentially promising method of implementing a quantum computer. This paper extends and further refines theoretical foundations and protocols for experimental implementation. We give a…

Quantum Physics · Physics 2015-05-13 Mile Gu , Christian Weedbrook , Nicolas C. Menicucci , Timothy C. Ralph , Peter van Loock

Coupled cluster methods based exclusively on double excitations are comparatively "cheap" and interesting model chemistries, as they are typically able to capture the bulk of the dynamical electron correlation effects. The trade-off in such…

Quantum Physics · Physics 2024-06-14 Zachary W. Windom , Daniel Claudino , Rodney J. Bartlett

In online clustering problems, there is often a large amount of uncertainty over possible cluster assignments that cannot be resolved until more data are observed. This difficulty is compounded when clusters follow complex distributions, as…

Machine Learning · Statistics 2026-04-17 Connie Trojan , Pavel Myshkov , Paul Fearnhead , James Hensman , Tom Minka , Christopher Nemeth
‹ Prev 1 3 4 5 6 7 10 Next ›