Non-autonomous Hamiltonian quantum systems, operator equations and representations of Bender-Dunne Weyl ordered basis under time-dependent canonical transformations

TL;DR

This paper develops methods to solve operator equations in non-autonomous quantum systems using time-dependent canonical transformations, focusing on the Bender-Dunne basis and explicit operator representations.

Contribution

It introduces a systematic approach for integrating operator equations via canonical transformations and derives explicit operator forms for basis transformations in quantum systems.

Findings

Successfully maps non-autonomous to autonomous Hamiltonians using time-dependent transformations

Derives generating functions for minimal series solutions in the Bender-Dunne basis

Provides explicit operators for basis transformations under canonical linear transformations

Abstract

We address the problem of integrating operator equations concomitant with the dynamics of non autonomous quantum systems by taking advantage of the use of time-dependent canonical transformations. In particular, we proceed to a discussion in regard to basic examples of one-dimensional non-autonomous dynamical systems enjoying the property that their Hamiltonian can be mapped through a time-dependent linear canonical transformation into an autonomous form, up to a time-dependent multiplicative factor. The operator equations we process essentially reproduce at the quantum level the classical integrability condition for these systems. Operator series form solutions in the Bender-Dunne basis of pseudo-differential operators for one dimensional quantum system are sought for such equations. The derivation of generating functions for the coefficients involved in the \emph{minimal} representation of the series solutions to the operator equations under consideration is particularized. We also provide explicit form of operators that implement arbitrary linear transformations on the Bender-Dunne basis by expressing them in terms of the initial Weyl ordered basis elements. We then remark that the matching of the minimal solutions obtained independently in the two basis, i.e. the basis prior and subsequent the action of canonical linear transformation, is perfectly achieved by retaining only the lowest order contribution in the expression of the transformed Bender-Dunne basis elements.