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Low temperature polaronic hopping conduction
Author(s) -
Thomas P.,
Wuertz D.
Publication year - 1978
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.2220860213
Subject(s) - condensed matter physics , seebeck coefficient , thermal conduction , conductivity , percolation (cognitive psychology) , density of states , debye model , electrical resistivity and conductivity , materials science , polaron , phonon , fermi level , physics , thermodynamics , electron , quantum mechanics , neuroscience , biology
The de‐hopping conductivity and thermopower is calculated for temperatures below half the Debye temperature θ D . A percolation approach with multiphonon hoprates is used. Two sets of energetically overlapping states near the Fermi level are consdered. The coupling to the phonons is assumed to be larger for the lower lying set of states. The resulting thermopower is negative and slowly varying with temperature, but bends down to higher neegative values at low (≈ 0.1θ D ) temperatures. The conductivity essentially follows a In σ ∼ T −1/4 law. The thermopower is much more stable with respect to changes in the density of states as compared to a model without multiphonon effects.