|
|
Instituto de Ciencia de Materiales de Madrid |
|
|||
| Condensed Matter Theory | |||||
| Sigmund Kohler | home | cv | research | publications | ||||
Hidden time-nonlocal Floquet symmetriesSigmund Kohler and Jesús Casado-PascualarXiv:2601.05783 We investigate the Floquet spectrum of a detuned, driven two-level system and show that it exhibits exact quasienergy crossings when the detuning is an integer multiple of the energy quantum of the driving field. This behavior can be explained by a hidden time-nonlocal parity, which allows the Floquet modes to be classified as even or odd. Then a generic feature is the emergence of exact crossings between quasienergies of different parity. A constructive proof of the existence of the symmetry is based on a scalar recurrence relation. Moreover, we present a general scheme for its numerical computation, which can be applied to models beyond the two-level system. Analytical results are illustrated with numerical data. |
[ICMM-CSIC]
[Condensed Matter Theory]
last modified: 13.1.2026 by
Sigmund Kohler