Dynamical structure functions, collective modes, and energy gap in charged-particle bilayers.
نویسندگان
چکیده
The dynamical properties of strongly coupled charged-particle bilayers are investigated by molecular dynamics (MD) simulation and theoretical analysis. The spectra of the current correlation functions show the existence of two (in-phase and out-of-phase) longitudinal and two (in-phase and out-of-phase) transverse collective modes. The out-of-phase modes possess finite frequencies at wave numbers k-->0, confirming the existence of the predicted long-wavelength energy gap in the bilayer system. A theoretical model based on an extended Feynman ansatz for the dynamical structure functions provides predictions on the strength of the collective modes that are verified by the MD experiment.
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ورودعنوان ژورنال:
- Physical review letters
دوره 90 22 شماره
صفحات -
تاریخ انتشار 2003