English
Related papers

Related papers: Scalable tensor network algorithm for quantum impu…

200 papers

Describing a quantum impurity coupled to one or more non-interacting fermionic reservoirs is a paradigmatic problem in quantum many-body physics. While historically the focus has been on the equilibrium properties of the impurity-reservoir…

Strongly Correlated Electrons · Physics 2023-05-10 Julian Thoenniss , Alessio Lerose , Dmitry A. Abanin

Quantum embedding theories provide a feasible route for obtaining quantitative descriptions of correlated materials. However, a critical challenge is solving an effective impurity model of correlated orbitals embedded in an electron bath.…

Strongly Correlated Electrons · Physics 2021-01-27 Hiroshi Shinaoka , Yuki Nagai

A continuous-time path integral Quantum Monte Carlo method using the directed-loop algorithm is developed to simulate the Anderson single-impurity model in the occupation number basis. Although the method suffers from a sign problem at low…

Strongly Correlated Electrons · Physics 2009-11-10 Jaebeom Yoo , Shailesh Chandrasekharan , Harold U. Baranger

We significantly enhance the simulation accuracy of initial Trotter circuits for Hamiltonian simulation of quantum systems by integrating first-order Riemannian optimization with tensor network methods. Unlike previous approaches, our…

Quantum Physics · Physics 2025-12-30 Isabel Nha Minh Le , Shuo Sun , Christian B. Mendl

This work builds upon previous efforts in online incremental learning, namely the Incremental Gaussian Mixture Network (IGMN). The IGMN is capable of learning from data streams in a single-pass by improving its model after analyzing each…

Machine Learning · Computer Science 2017-02-08 Rafael Pinto , Paulo Engel

Integer programming (IP) is an NP-hard combinatorial optimization problem that is widely used to represent a diverse set of real-world problems spanning multiple fields, such as finance, engineering, logistics, and operations research. It…

Quantum Physics · Physics 2025-08-20 Kapil Goswami , Peter Schmelcher , Rick Mukherjee

We introduce a scalable approach to Gaussian process inference that combines spatio-temporal filtering with natural gradient variational inference, resulting in a non-conjugate GP method for multivariate data that scales linearly with…

Machine Learning · Computer Science 2021-11-03 Oliver Hamelijnck , William J. Wilkinson , Niki A. Loppi , Arno Solin , Theodoros Damoulas

We develop a diagrammatic Monte Carlo method for the real-time dynamics of dissipative quantum impurity models. These are small open quantum systems with interaction and local Markovian dissipation, coupled to a large quantum bath. Our…

Strongly Correlated Electrons · Physics 2024-03-26 Matthieu Vanhoecke , Marco Schirò

Kalman filtering and smoothing are the foundational mechanisms for efficient inference in Gauss-Markov models. However, their time and memory complexities scale prohibitively with the size of the state space. This is particularly…

Machine Learning · Computer Science 2025-03-13 Marvin Pförtner , Jonathan Wenger , Jon Cockayne , Philipp Hennig

We present a diagrammatic Monte Carlo method for quantum impurity problems with general interactions and general hybridization functions. Our method uses a recursive determinant scheme to sample diagrams for the scattering amplitude. Unlike…

Strongly Correlated Electrons · Physics 2020-08-13 Jia Li , Markus Wallerberger , Emanuel Gull

Neutrino transport in compact objects is an inherently challenging multi-dimensional problem. This difficulty is compounded if one includes flavor transformation -- an intrinsically quantum phenomenon requiring one to follow the coherence…

High Energy Astrophysical Phenomena · Physics 2025-05-14 Evan Grohs , Sherwood Richers , Julien Froustey , Francois Foucart , James P. Kneller , Gail C. McLaughlin

In the $0+1$ dimensional imaginary-time path integral formulation of quantum impurity problems, the retarded action encodes the hybridization of the impurity with the bath. In this Article, we explore the computational power of representing…

In the present paper, we present an efficient continuous-time quantum Monte Carlo impurity solver with high acceptance rate at low temperature for multi-orbital quantum impurity models with general interaction. In this hybridization…

Strongly Correlated Electrons · Physics 2019-02-20 Changming Yue , Yilin Wang , Junya Otsuki , Xi Dai

We describe an open-source implementation of the continuous-time hybridization-expansion quantum Monte Carlo method for impurity models with general instantaneous two-body interactions and complex hybridization functions. The code is built…

Strongly Correlated Electrons · Physics 2017-05-02 Hiroshi Shinaoka , Emanuel Gull , Philipp Werner

Running quantum algorithms often involves implementing complex quantum circuits with such a large number of multi-qubit gates that the challenge of tackling practical applications appears daunting. To date, no experiments have successfully…

We introduce the Markovian matrix product density operator, which is a special subclass of the matrix product density operator. We show that the von Neumann entropy of such ansatz can be computed efficiently on a classical computer. This is…

Quantum Physics · Physics 2017-09-28 Isaac H. Kim

Tensor networks and quantum computation are two of the most powerful tools for the simulation of quantum many-body systems. Rather than viewing them as competing approaches, here we consider how these two methods can work in tandem. We…

Tensor network techniques are becoming increasingly popular tools to solve partial differential equations within the so-called quantics representation. Their popularity stems from the fact that their spatial resolution depends only…

Quantum Physics · Physics 2026-04-13 Jheng-Wei Li , Nicolas Jolly , Xavier Waintal

An efficient quantum algorithm is proposed to solve in polynomial time the parity problem, one of the hardest problems both in conventional quantum computation and in classical computation, on NMR quantum computers. It is based on the…

Quantum Physics · Physics 2007-05-23 Xijia Miao

An acceleration of continuous time quantum Monte Carlo (CTQMC) methods is a potentially interesting branch of work as they are matchless as impurity solvers of a density functional theory in combination with a dynamical mean field theory…

Strongly Correlated Electrons · Physics 2019-08-07 Taegeun Song , Hunpyo Lee