Changes in Floquet State Structure at Avoided Crossings: Delocalization and Harmonic Generation
نویسندگان
چکیده
Avoided crossings are common in the quasienergy spectra of strongly driven nonlinear quantum wells. In this paper we examine the sinusoidally driven particle in a square potential well to show that avoided crossings can alter the structure of Floquet states in this system. Two types of avoided crossings are identi ed: one type leads only to temporary changes (as a function of driving eld strength) in Floquet state structure while the second type can lead to permanent delocalization of the Floquet states. Radiation spectra from these latter states show a signi cant increase in high harmonic generation as the system passes through the avoided crossing.
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