title: Ferrotoroidic moment as a quantum geometric phase.
abstract: We present a geometric characterization of the ferrotoroidic moment tau in terms of a set of Abelian Berry phases. We also introduce a fundamental complex quantity z munu, which provides an alternative way to calculate tau and its moments and is derived from the tensor T munu=2 under summation operator jrj muSj nu. This geometric framework defines a natural computational approach for density functional and many-body theories.
authors.affiliation: Theoretical Division, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545, USA.
authors.forename: C D
authors.initials: CD
authors.lastname: Batista
authors.forename: G
authors.initials: G
authors.lastname: Ortiz
authors.forename: A A
authors.initials: AA
authors.lastname: Aligia