238 research outputs found
Low-temperature thermal conductivity in polycrystalline graphene
The low-temperature thermal conductivity in polycrystalline graphene is
theoretically studied. The contributions from three branches of acoustic
phonons are calculated by taking into account scattering on sample borders,
point defects and grain boundaries. Phonon scattering due to sample borders and
grain boundaries is shown to result in a -behaviour in the thermal
conductivity where varies between 1 and 2. This behaviour is found to
be more pronounced for nanosized grain boundaries.
PACS: 65.80.Ck, 81.05.ue, 73.43.C
Electron scattering due to dislocation wall strain field in GaN layers
The effect of edge-type dislocation wall strain field on the Hall mobility in
n-type epitaxial GaN was theoretically investigated through deformation
potential within the relaxation time approach. It was found that this channel
of scattering can play a considerable role in the low-temperature transport at
the certain set of the model parameters. The low temperature experimental data
were fitted by including this mechanism of scattering along with ionized
impurities and charge dislocation ones
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