Diagrammatic Monte Carlo approach to angular momentum in quantum many-particle systems Journal Article


Author(s): Bighin, Giacomo; Tscherbul, Timur V; Lemeshko, Mikhail P
Article Title: Diagrammatic Monte Carlo approach to angular momentum in quantum many-particle systems
Affiliation IST Austria
Abstract: We introduce a diagrammatic Monte Carlo approach to angular momentum properties of quantum many-particle systems possessing a macroscopic number of degrees of freedom. The treatment is based on a diagrammatic expansion that merges the usual Feynman diagrams with the angular momentum diagrams known from atomic and nuclear structure theory, thereby incorporating the non-Abelian algebra inherent to quantum rotations. Our approach is applicable at arbitrary coupling, is free of systematic errors and of finite-size effects, and naturally provides access to the impurity Green function. We exemplify the technique by obtaining an all-coupling solution of the angulon model; however, the method is quite general and can be applied to a broad variety of systems in which particles exchange quantum angular momentum with their many-body environment.
Journal Title: Physical Review Letters
Volume: 121
Issue 16
ISSN: 1079-7114
Publisher: American Physical Society  
Date Published: 2018-10-16
Start Page: Article number: 165301
DOI: 10.1103/PhysRevLett.121.165301
Open access: no