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Related papers: Linear-scaling electronic structure theory: Electr…

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The past years have witnessed impressive advances in electronic structure calculation, especially in the complexity and size of the systems studied, as well as in computation time. Linear scaling methods based on empirical tight-binding…

Materials Science · Physics 2007-05-23 Abduxukur Abdurixit , Alexis Baratoff , Giulia Galli

The Kohn-Sham scheme of density functional theory is one of the most widely used methods to solve electronic structure problems for a vast variety of atomistic systems across different scientific fields. While the method is fast relative to…

We present a variational density matrix approach to the thermal properties of interacting fermions in the continuum. The variational density matrix is parametrized by a permutation equivariant many-body unitary transformation together with…

Strongly Correlated Electrons · Physics 2022-04-04 Hao Xie , Linfeng Zhang , Lei Wang

We present a quantum thermometric protocol for the estimation of multiple temperatures within the collisional model framework. Employing the formalism of multiparameter quantum metrology, we develop a systematic strategy to estimate the…

Quantum Physics · Physics 2025-11-26 Srijon Ghosh , Sagnik Chakraborty , Rosario Lo Franco

Simulating electronic behavior in materials and devices with realistic large system sizes remains a formidable task within the $ab$ $initio$ framework due to its computational intensity. Here we show DeePTB, an efficient deep learning-based…

Materials Science · Physics 2024-11-14 Qiangqiang Gu , Zhanghao Zhouyin , Shishir Kumar Pandey , Peng Zhang , Linfeng Zhang , Weinan E

This paper investigates a new formalism to describe real time evolution of quantum systems at finite temperature. A time correlation function among subsystems will be derived which allows for a probabilistic interpretation. Our derivation…

High Energy Physics - Theory · Physics 2009-10-31 E. Mendel , M. Nest

An overview of computational methods to describe high-dimensional potential energy surfaces suitable for atomistic simulations is given. Particular emphasis is put on accuracy, computability, transferability and extensibility of the methods…

Chemical Physics · Physics 2020-07-08 Oliver T. Unke , Debasish Koner , Sarbani Patra , Silvan Käser , Markus Meuwly

Many phenomena of strongly correlated materials are encapsulated in the Fermi-Hubbard model whose thermodynamical properties can be computed from its grand canonical potential according to standard procedures. In general, there is no closed…

Quantum Physics · Physics 2016-03-09 Pierre-Luc Dallaire-Demers , Frank K. Wilhelm

Heat diffusion has been widely used in brain imaging for surface fairing, mesh regularization and cortical data smoothing. Motivated by diffusion wavelets and convolutional neural networks on graphs, we present a new fast and accurate…

Computer Vision and Pattern Recognition · Computer Science 2020-01-20 Shih-Gu Huang , Ilwoo Lyu , Anqi Qiu , Moo K. Chung

We show here that the Hamiltonian for an electronic system may be written exactly in terms of fluctuation operators that transition constituent fragments between internally correlated states, accounting rigorously for inter-fragment…

Chemical Physics · Physics 2019-05-24 Anthony D. Dutoi , Yuhong Liu

We present a novel "linear combination of atomic orbitals"-type of approximation, enabling accurate electronic structure calculations for systems of up to 20 or more electronically coupled quantum dots. Using realistic single quantum dot…

Mesoscale and Nanoscale Physics · Physics 2021-03-10 Alexander Mittelstädt , Ludwig A. Th. Greif , Stefan T. Jagsch , Andrei Schliwa

We introduce machine learning (ML) models that predict the electronic structure of materials across a wide temperature range. Our models employ neural networks and are trained on density functional theory (DFT) data. Unlike most other ML…

Materials Science · Physics 2023-10-02 Lenz Fiedler , Normand A. Modine , Kyle D. Miller , Attila Cangi

Recently, machine learning had a remarkable impact, from scientific to everyday-life applications. However, complex tasks often imply unfeasible energy and computational power consumption. Quantum computation might lower such requirements,…

On the basis of ab initio quantum mechanics (QM) calculation, the obtained electron heat capacity is implemented into energy equation of electron subsystem in two temperature model (TTM). Upon laser irradiation on the copper film, energy…

Chemical Physics · Physics 2016-03-01 Pengfei Ji , Yuwen Zhang

Large scale Density Functional Theory (DFT) based electronic structure calculations are highly time consuming and scale poorly with system size. While semi-empirical approximations to DFT result in a reduction in computational time versus…

Materials Science · Physics 2016-12-21 Ganesh Hegde , R. Chris Bowen

This paper proposes a higher-order multiscale computational method for nonlinear thermo-electric coupling problems of composite structures, which possess temperature-dependent material properties and nonlinear Joule heating. The innovative…

Numerical Analysis · Mathematics 2025-01-24 Hao Dong , Zongze Yang , Yufeng Nie

In this paper, we show that efficient separated sum-of-exponentials approximations can be constructed for the heat kernel in any dimension. In one space dimension, the heat kernel admits an approximation involving a number of terms that is…

Numerical Analysis · Mathematics 2013-08-20 Shidong Jiang , Leslie Greengard , Shaobo Wang

In this paper we develop a quantum algorithm to realize finite temperature simulation on a quantum computer. As quantum computers use real-time evolution we did not use the imaginary time methods popular on classical algorithms. Instead, we…

Quantum Physics · Physics 2019-11-11 Raffaele Miceli , Michael McGuigan

The minimally entangled typical thermal states algorithm is applied to fermionic systems using the Krylov-space approach to evolve the system in imaginary time. The convergence of local observables is studied in a tight-binding system with…

Strongly Correlated Electrons · Physics 2013-07-31 G. Alvarez

Linear programming is used as a standard tool for optimising unit commitment or power flows in energy supply systems. For heat supply systems, however, it faces a relevant limitation: For them, energy yield depends on the output…