Disordered binary harmonic chains with site-dependent force constants
نویسنده
چکیده
A hierarchical lattice model for a disordered two-component one-dimensional harmonic chain with three force constants, corresponding to the three possible pairs of nearest neighbors, is studied. Differences of as little as 20% between the various force constants can appreciably modify the density of states. These changes in the spectrum allow one to roughly characterize which type of interaction and which atoms are involved in the eigenmodes contained in certain frequency ranges.
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تاریخ انتشار 2011