Excited eigenstates and strength functions for isolated systems of interacting particles

1998/12/29 by V. V. Flambaum, F. M. Izrailev
Physics and Astronomy · #Atomic physics #Cold Atom Physics and Bose-Einstein Condensates #Eigenvalues and eigenvectors #Excited state #Laser-Matter Interactions and Applications #Physics #Quantum chaos and dynamical systems #Quantum mechanics #chao-dyn #cond-mat.dis-nn #cond-mat.mes-hall #cond-mat.stat-mech #nlin.CD #nucl-th #quant-ph

paper · pdf · doi:10.1103/physreve.61.2539

published as Phys.Rev.E61:2539,2000 · 4 pages in RevTex and 1 Postscript figure

arxiv created 1998/12/29 · openalex publication_date 2000/03/01 · arxiv updated 2016/08/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Eigenstates in finite systems such as heavy nuclei and atoms, atomic clusters and quantum dots with few excited particles are known to be chaotic superposition of shell model basis states. Here we develop a method for description of this kind of eigenstates (ES) as well as of strength functions (SF). Using the model of n randomly interacting particles distributed over m orbitals we show that the average form of ES and SF in energy representation is given by the Breit-Wigner formula with the width \ensuremathΓ which has a Gaussian dependence on energy. This explains evolution of ES and SF from the Breit-Wigner form for weak interaction to Gaussian form for strong interaction.

Citations

• Quasiparticle Lifetime in a Finite System: A Nonperturbative Approach
• Distribution of occupation numbers in finite Fermi systemsand role of interaction in chaos and thermalization
• Localization and fluctuations of local spectral density on treelike structures with large connectivity: Application to the quasiparticle line shape in quantum dots
• Towards a statistical theory of finite Fermi systems and compound states: Random two-body interaction approach