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Related papers: Many-body theory of positron-atom interactions

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As part of our program to develop the description of three-body effects in quantum vacuum phenomena, we study the three-body interaction of two anisotropically polarizable atoms with a perfect electrically conducting plate, a generalization…

Quantum Physics · Physics 2022-03-02 Kimball A. Milton , Elom Abalo , Prachi Parashar , K. V. Shajesh

We develop a theory for light propagating in an atomic Bose-Einstein condensate in the presence of strong interactions. The resulting many-body correlations are shown to have profound effects on the optical properties of this interacting…

Quantum Gases · Physics 2020-05-06 A. Camacho-Guardian , K. Knakkergaard Nielsen , T. Pohl , G. M. Bruun

Many quantal many-body methods that aim at the description of self-bound nuclear or mesoscopic electronic systems make use of auxiliary wave functions that break one or several of the symmetries of the Hamiltonian in order to include…

Nuclear Theory · Physics 2021-02-16 Benjamin Bally , Michael Bender

We use the composite boson (coboson) many-body formalism to tackle scattering lengths for cold fermionic atoms. We show that bound dimers can be taken as elementary entities provided that fermion exchanges between them are treated exactly,…

Quantum Gases · Physics 2018-12-11 Shiue-Yuan Shiau , Ching-Hang Chien , Yia-Chung Chang , Monique Combescot

Entanglement entropy is a measure of quantum correlations between separate parts of a many-body system, which plays an important role in many areas of physics. Here we review recent work in which a relation between this quantity and the…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Israel Klich , Leonid Levitov

A model-potential approach to calculating positron-molecule binding energies and annihilation rates is developed. Unlike existing ab initio calculations, which have mostly been applied to strongly polar molecules, the present methodology…

Atomic Physics · Physics 2018-12-31 A. R. Swann , G. F. Gribakin

The linear-response theory of the multiconfigurational time-dependent Hartree for bosons method for computing many-body excitations of trapped Bose-Einstein condensates [Phys. Rev. A {\bf 88}, 023606 (2013)] is implemented for systems with…

Quantum Gases · Physics 2015-03-24 Ofir E. Alon

A framework for developing new approximate electronic structure methods is presented, in which the correlation energy of a many-electron system in the ground state is computed as in the single-reference second-order many-body perturbation…

Chemical Physics · Physics 2011-06-15 Dimitri Laikov

In quantum many-body theory, all physical observables are described in terms of correlation functions between particle creation/annihilation operators. Measurement of such correlation functions can therefore be regarded as an operational…

An explicit expression for the quadratic density-response function of a many-electron system is obtained in the framework of the time-dependent density-functional theory, in terms of the linear and quadratic density-response functions of…

Materials Science · Physics 2009-11-10 V. U. Nazarov , J. M. Pitarke , C. S. Kim , Y. Takada

We develop a general method for constructing the many-body Hamiltonian of pairwise interactions describing homonuclear mixtures of atoms occupying states with different total angular momenta or other quantum numbers. The advantage of the…

Quantum Gases · Physics 2026-05-22 M. Bulakhov , A. S. Peletminskii , Yu. V. Slyusarenko

We introduce a new computational method to study porphyrin-like transition metal complexes, bridging density functional theory and exact many-body techniques, such as the density matrix renormalization group (DMRG). We first derive a…

Mesoscale and Nanoscale Physics · Physics 2019-06-13 Andrew Allerdt , Hasnain Hafiz , Bernardo Barbiellini , Arun Bansil , Adrian E. Feiguin

Conductivity models for warm dense matter inform simulations of planetary structure and fusion experiments. State-of-the-art conductivity calculations based on density functional theory approximate many-body physics and neglect…

The positron-hydrogen atom scattering system is considered within the S-wave model. Convergence in the elastic scattering, excitation, ionization, and positronium formation channels is studied as a function of the number and type of states…

Atomic Physics · Physics 2009-10-31 Alisher S. Kadyrov , Igor Bray

The exact solution of a diffusion$-$reaction model for the trapping and annihilation of positrons at interfaces of precipitate$-$matrix composites is presented considering both cylindrical or spherical precipitates. Diffusion-limitation is…

Soft Condensed Matter · Physics 2020-01-29 Roland Würschum , Laura Resch , Gregor Klinser

In this paper we study an archetypical scenario in which repulsive Casimir-Polder forces between an atom or molecule and two macroscopic bodies can be achieved. This is an extension of previous studies of the interaction between a…

Four point correlation functions for many electrons at finite temperature in periodic lattice are analyzed by the perturbation theory with respect to the coupling constant. The correlation functions are characterized as a limit of finite…

Mathematical Physics · Physics 2015-05-13 Yohei Kashima

We develop a theoretical method within the framework of relativistic many-body theory to accurately treat correlation corrections in atoms with few valence electrons. This method combines the all-order approach currently used in precision…

Atomic Physics · Physics 2009-09-01 M. S. Safronova , M. G. Kozlov , W. R. Johnson , Dansha Jiang

A self-consistent many-body approach is proposed to build a first-principles crystal field theory, where crystal field parameters are calculated ab initio. Many-body theory is used to write the energy of the interacting system as a function…

Strongly Correlated Electrons · Physics 2010-09-17 Christian Brouder

Over the last decade, new developments in Similarity Renormalization Group techniques and nuclear many-body methods have dramatically increased the capabilities of ab initio nuclear structure and reaction theory. Ground and excited-state…

Nuclear Theory · Physics 2020-10-09 H. Hergert