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arXiv · 1506.01541

Some properties of Grassmannian $U(4)/U(2)^2$ coherent states and an entropic conjecture

Manuel Calixto·Emilio Perez-Romero
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Abstract

We analyze mathematical and physical properties of a previously introduced [J. Phys. A47, 115302 (2014)] family of $U(4)$ coherent states (CS). They constitute a matrix version of standard spin $U(2)$ CS when we add an extra (pseudospin) dichotomous degree of freedom: layer, sublattice, two-well, nucleon, etc. Applications to bilayer quantum Hall systems at fractions of filling factor $\nu=2$ are discussed, where Haldane's sphere picture is generalized to a Grassmannian picture. We also extend Wehrl's definition of entropy from Glauber to Grassmannian CS and state a conjecture on the entropy lower bound.

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Manuel Calixto, Emilio Perez-Romero. 2015-06-04. Some properties of Grassmannian $U(4)/U(2)^2$ coherent states and an entropic conjecture. https://doi.org/10.1088/1751-8113/48/49/495304

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