Gelfand-Tsetlin bases of representations for super Yangian and quantum affine superalgebra
Kang Lu
TL;DR
The paper develops explicit Gelfand-Tsetlin bases for skew representations of the super Yangian $Y(\mathfrak{gl}_{m|n})$ and derives exact actions of Drinfeld generators on these bases, proving irreducibility of skew representations. It introduces and leverages the Gelfand-Tsetlin algebra $\mathrm{A}(\mathfrak{gl}_{m|n})$ to define and analyze tame and thin modules, and furnishes a complete description for $Y(\mathfrak{gl}_{1|1})$ tameness. Extending the framework to the quantum affine superalgebra $U_q(\widehat{\mathfrak{gl}}_{m|n})$, the authors provide analogous GT-based Irreducibility results for skew representations, including evaluation morphisms, $\ell$-weights, and explicit action formulas. The work thereby unifies and advances understanding of GT bases, explicit current actions, and the pole structure in both the classical and quantum supersymmetric settings, with potential implications for tame module classifications and connections to related algebras.
Abstract
We give explicit actions of Drinfeld generators on Gelfand-Tsetlin bases of super Yangian modules associated with skew Young diagrams. In particular, we give another proof that these representations are irreducible. We study irreducible tame $\mathrm Y(\mathfrak{gl}_{1|1})$-modules and show that a finite-dimensional irreducible $\mathrm Y(\mathfrak{gl}_{1|1})$-module is tame if and only if it is thin. We also give the analogous statements for quantum affine superalgebra of type A.
