Quantum super Schur--Weyl duality and character formulas for mirabolic Hecke algebras

Source abstract

We establish a quantum super Schur--Weyl duality for the mirabolic Hecke algebra $H_n^{\mathrm{mir}}(q)$ with $q$ indeterminate and determine the corresponding bimodule decomposition. The centralizer of the mirabolic action is shown as a direct sum of homogeneous quantum Schur superalgebras. We describe the tensor-space annihilator and the resulting faithful quotient. When nonzero, the annihilator is generated by an explicit spectral idempotent attached to the smallest rectangle excluded by the hook condition. From the quantum super Schur--Weyl duality, we derive a super Frobenius formula for mirabolic Hecke algebras. This formula then yields a Murnaghan--Nakayama rule and Regev-type formulas for the irreducible characters. We also construct a super mirabolic RSK bijection from words in a super alphabet with an additional even letter to hook semistandard insertion tableaux together with recording pairs that distinguish the positions of the additional letter. This correspondence yields a Roichman formula for irreducible characters of $H_n^{\mathrm{mir}}(q)$. Finally, we establish a parameter-inversion isomorphism between $H_n^{\mathrm{mir}}(q^{-1})$ and the $q$-rook monoid algebra $R_n(q)$ and use it to transport the duality, annihilators, and character formulas in both directions. The transported tensor decomposition provides a representation-theoretic interpretation of hook and two-row character sums for $R_n(q)$.