Higher-order supersymmetry in quantum mechanics and integrability of two-dimensional Hamiltonians

A new method of finding the dynamic symmetry operators in two-dimensional quantum systems is proposed. This method is based on the SUSY algebra with superchanges of higher order in derivatives. The symmetry operators arise when closing the SUSY algebra for a wide class of potentials, and, in some cases, they are of second order in derivatives. The solutions for potentials admitting symmetry operators of fourth order are also obtained. The investigation of the quasiclassical limit of the superalgebra results in new classical integrals of motion for a certain type of systems. Bibliography: 9 titles.