Two-parameter asymptotics in magnetic Weyl calculus

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)

Abstract

This paper is concerned with small parameter asymptotics of magnetic quantum systems. In addition to a semiclassical parameter ε, the case of small coupling λ to the magnetic vector potential naturally occurs in this context. Magnetic Weyl calculus is adapted to incorporate both parameters, at least one of which needs to be small. Of particular interest is the expansion of the Weyl product which can be used to expand the product of operators in a small parameter, a technique which is prominent to obtain perturbation expansions. Three asymptotic expansions for the magnetic Weyl product of two HÖrmander class symbols are proven as (i) ε ≪ 1 and λ ≪ 1, (ii) ε ≪ 1 and λ = 1, as well as (iii) ε = 1 and λ ≪ 1. Expansions (i) and (iii) are impossible to obtain with ordinary Weyl calculus. Furthermore, I relate the results derived by ordinary Weyl calculus with those obtained with magnetic Weyl calculus by one- and two-parameter expansions. To show the power and versatility of magnetic Weyl calculus, I derive the semirelativistic Pauli equation as a scaling limit from the Dirac equation up to errors of fourth order in 1/c.

Original languageEnglish
Article number123519
JournalJournal of Mathematical Physics
Volume51
Issue number12
DOIs
Publication statusPublished - 2010 Dec 1
Externally publishedYes

ASJC Scopus subject areas

  • Statistical and Nonlinear Physics
  • Mathematical Physics

Fingerprint Dive into the research topics of 'Two-parameter asymptotics in magnetic Weyl calculus'. Together they form a unique fingerprint.

Cite this