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arXiv · 0810.2823

Intrinsic Localized Modes Observed in the High Temperature Vibrational Spectrum of NaI

M. E. Manley·A. J. Sievers·J. W. Lynn·S. A. Kiselev·N. I. Agladze·Y. Chen·A. Llobet·A. Alatas
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Abstract

Inelastic neutron measurements of the high-temperature lattice excitations in NaI show that in thermal equilibrium at 555 K an intrinsic mode, localized in three dimensions, occurs at a single frequency near the center of the spectral phonon gap, polarized along [111]. At higher temperatures the intrinsic localized mode gains intensity. Higher energy inelastic neutron and x-ray scattering measurements on a room-temperature NaI crystal indicate that the creation energy of the ground state of the intrinsic localized mode is 299 meV.

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M. E. Manley, A. J. Sievers, J. W. Lynn, S. A. Kiselev, N. I. Agladze, Y. Chen, A. Llobet, A. Alatas. 2009-04-30. Intrinsic Localized Modes Observed in the High Temperature Vibrational Spectrum of NaI. https://doi.org/10.1103/physrevb.79.134304

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