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تسجيل مستخدم جديدSome properties of Grassmannian $U(4)/U(2)^2$ coherent states and an entropic conjecture
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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 $ u=2$ are discussed, where Haldanes sphere picture is generalized to a Grassmannian picture. We also extend Wehrls definition of entropy from Glauber to Grassmannian CS and state a conjecture on the entropy lower bound.
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Bilayer quantum Hall (BLQH) systems, which underlie a $U(4)$ symmetry, display unique quantum coherence effects. We study coherent states (CS) on the complex Grassmannian $mathbb G_2^4=U(4)/U(2)^2$, orthonormal basis, $U(4)$ generators and their matr
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