Semiclassical analysis of tunnelling splittings in periodically driven quantum systems
نویسندگان
چکیده
For periodically driven systems, quantum tunnelling between classical resonant stability islands in phase space separated by invariant KAM curves or chaotic regions manifests itself by oscillatory motion of wavepackets centred on such an island, by mulitplet splittings of the quasienergy spectrum, and by phase space localization of the quasienergy states on symmetryrelated flux tubes. Qualitatively different types of classical resonant island formation—due to discrete symmetries of the system—and their quantum implications are analysed by a (uniform) semiclassical theory. The results are illustrated by a numerical study of a driven non-harmonic oscillator.
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