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The dielectric response and structural properties of finite-temperature electron liquids are central to accurately describing the physical behavior of electronic systems. This study presents a robust analytical model for the static…

Plasma Physics · Physics 2026-03-19 Chengliang Lin , Yong Hou , Jianmin Yuan , Yong Wu , Jianguo Wang

We show that the energy of a perturbed system can be fully recovered from the unperturbed system's electron density. We derive an alchemical integral transform by parametrizing space in terms of transmutations, the chain rule and…

Chemical Physics · Physics 2022-10-28 Simon León Krug , Guido Falk von Rudorff , O. Anatole von Lilienfeld

Modern density functional approximations achieve moderate accuracy at low computational cost for many electronic structure calculations. Some background is given relating the gradient expansion of density functional theory to the WKB…

Chemical Physics · Physics 2021-01-27 Kieron Burke

We modify the Green operator involved in Fourier-based computational schemes in elasticity, in 2D and 3D. The new operator is derived by expressing continuum mechanics in terms of centered differences on a rotated grid. Use of the modified…

Numerical Analysis · Mathematics 2015-02-20 François Willot

Calculations of ground-state and excited-state properties of materials have been one of the major goals of condensed matter physics. Ground-state properties of solids have been extensively investigated for several decades within the…

Strongly Correlated Electrons · Physics 2009-10-30 F. Aryasetiawan , O. Gunnarsson

We suggest a new method of calculation of the equilibrium correlation functions of an arbitrary order for the interacting Fermi-gas model in the frame of the static fluctuation approximation (SFA) method. This method based only on the…

Strongly Correlated Electrons · Physics 2015-05-27 R. R. Nigmatullin , A. A. Khamzin , I. I. Popov

We have applied the Fast Fourier transform (FFT), which allows to compute efficiently convolution sums, to solve the set of self-consistent T-matrix equations to get the Green function of the two dimensional attractive-U Hubbard modelbelow…

Superconductivity · Physics 2009-10-28 S. Schafroth , J. J. Rodriguez , H. Beck

We present the first hardware implementation of electrostatic interaction energies using a trapped-ion quantum computer. As test system for our computation, we focus on the reduction of $\mathrm{NO}$ to $\mathrm{N}_2\mathrm{O}$ catalyzed by…

Dynamical mass generation in a three-dimensional version of finite-temperature QED is studied with the help of Schwinger-Dyson equations in the real-time formalism. We go beyond the bare-vertex approximation and include wave-function…

High Energy Physics - Phenomenology · Physics 2009-10-31 George Triantaphyllou

Simulation of warm dense matter requires computational methods that capture both quantum and classical behavior efficiently under high-temperature, high-density conditions. Currently, density functional theory molecular dynamics is used to…

Chemical Physics · Physics 2015-10-21 Attila Cangi , Aurora Pribram-Jones

In this work, we develop a method for rational approximation of the Fourier transform (FT) based on the real and imaginary parts of the complex error function \[ w(z) = e^{-z^2}(1 - {\rm{erf}}(-iz)) = K(x,y) + iL(x,y), \qquad z = x + iy, \]…

General Mathematics · Mathematics 2025-06-25 Sanjar M. Abrarov , Rehan Siddiqui , Rajinder K. Jagpal , Brendan M. Quine

The electron and photon transport processes in spectroscopy techniques described by the invariant embedding theory is here revisited. We report a convergence method to obtain closed analytical solutions to the 3D integro-differential…

Materials Science · Physics 2010-06-22 Carlos Figueroa , Horacio Brizuela , Silvia P. Heluani

Exploratory variational pseudopotential density functional calculations are performed for the electronic properties of many-electron systems in the 3D cartesian coordinate grid (CCG). The atom-centered localized gaussian basis set,…

Chemical Physics · Physics 2015-05-18 Amlan K Roy

A new approximation method for inverting the Poisson's equation is presented for a continuously distributed and finite-sized source in an unbound domain. The advantage of this image multipole method arises from its ability to place the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 James H. H. Chan , Tzihong Chiueh

We provide a comprehensive theoretical framework for describing the dynamics of a single trapped ion interacting with a neutral buffer gas, thus extending our previous studies on buffer-gas cooling of ions beyond the critical mass ratio [B.…

We employ Non-equilibrium Green's functions (NEGF) to describe the real-time dynamics of an adsorbate-surface model system exposed to ultrafast laser pulses. For a finite number of electronic orbitals, the system is solved exactly and…

Mesoscale and Nanoscale Physics · Physics 2016-05-04 E. Boström , M. Hopjan , A. Kartsev , C. Verdozzi , C. -O. Almbladh

In the nonequilibrium Green's function approach, the approximation of the correlation self-energy at the second-Born level is of particular interest, since it allows for a maximal speed-up in computational scaling when used together with…

Computational Physics · Physics 2019-11-11 Riku Tuovinen , Fabio Covito , Michael A. Sentef

The complex wave representation (CWR) converts unsigned 2D distance transforms into their corresponding wave functions. Here, the distance transform S(X) appears as the phase of the wave function \phi(X)---specifically,…

Machine Learning · Statistics 2013-02-06 Karthik S. Gurumoorthy , Anand Rangarajan

Problems of finite-temperature quantum statistical mechanics can be formulated in terms of imaginary (Euclidean) -time Green's functions and self-energies. In the context of realistic Hamiltonians, the large energy scale of the Hamiltonian…

Statistical Mechanics · Physics 2018-08-17 Emanuel Gull , Sergei Iskakov , Igor Krivenko , Alexander A. Rusakov , Dominika Zgid

We present an approach for self-consistent calculations of the many-body Green function in transition metals. The distinguishing feature of our approach is the use of the one-site approximation and the self-consistent quasiparticle wave…

Strongly Correlated Electrons · Physics 2009-11-07 N. E. Zein , V. P. Antropov