Rotation of quantum impurities in the presence of a many-body environment Journal Article


Author(s): Schmidt, Richard; Lemeshko, Mikhail P
Article Title: Rotation of quantum impurities in the presence of a many-body environment
Affiliation IST Austria
Abstract: We develop a microscopic theory describing a quantum impurity whose rotational degree of freedom is coupled to a many-particle bath. We approach the problem by introducing the concept of an “angulon”—a quantum rotor dressed by a quantum field—and reveal its quasiparticle properties using a combination of variational and diagrammatic techniques. Our theory predicts renormalization of the impurity rotational structure, such as that observed in experiments with molecules in superfluid helium droplets, in terms of a rotational Lamb shift induced by the many-particle environment. Furthermore, we discover a rich many-body-induced fine structure, emerging in rotational spectra due to a redistribution of angular momentum within the quantum many-body system.
Journal Title: Physical Review Letters
Volume: 114
ISSN: 1079-7114
Publisher: American Physical Society  
Date Published: 2015-05-18
Start Page: Article number: 203001
URL:
DOI: 10.1103/PhysRevLett.114.203001
Notes: The work was supported by the NSF through a grant for the Institute for Theoretical Atomic, Molecular, and Optical Physics at Harvard University and the Smithsonian Astrophysical Observatory.
Open access: yes (repository)