Floquet Product Mode

Results are presented for the dynamics of edge modes in interacting Floquet Ising chains. It is shown that in addition to the quasi-stable $0$ and $\pi$ edge modes, a third long lived edge mode arising from the operator product of the $0$ and $\pi$ edge modes exists. Depending on the microscopic parameters, this Floquet product mode is shown to have a substantially longer lifetime than the individual $0$ and $\pi$ modes. This is triggered by a scattering process which converts a $0$ mode into a $\pi$ mode while scattering two bulk excitations. This process can lead to a rapid decay of both $0$ and $\pi$ mode without affecting the product mode.