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arXiv · 1810.10281

A Solvable Model for Decoupling of Interacting Clusters

Artem G. Volosniev·Aksel S. Jensen·Nathan L. Harshman·Jeremy R. Armstrong·Nikolaj T. Zinner
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Abstract

We consider M clusters of interacting particles, whose in-group interactions are arbitrary, and inter-group interactions are approximated by oscillator potentials. We show that there are masses and frequencies that decouple the in-group and inter-group degrees of freedom, which reduces the initial problem to M independent problems that describe each of the relative in-group systems. The dynamics of the M center-of-mass coordinates is described by the analytically solvable problem of M coupled harmonic oscillators. This paper derives and discusses these decoupling conditions. Furthermore, to illustrate our findings, we consider a charged impurity interacting with a ring of ions. We argue that the impurity can be used to probe the center-of-mass dynamics of the ions.

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Artem G. Volosniev, Aksel S. Jensen, Nathan L. Harshman, Jeremy R. Armstrong, Nikolaj T. Zinner. 2018-10-24. A Solvable Model for Decoupling of Interacting Clusters. https://doi.org/10.1209/0295-5075%2F125%2F20003

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