Open AccessCoulomb gap and variable range hopping in a pinned Wigner crystal
Author(s) -
Shklovskii B. I.
Publication year - 2004
Publication title -
physica status solidi (c)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 46
eISSN - 1610-1642
pISSN - 1610-1634
DOI - 10.1002/pssc.200303642
Subject(s) - wigner crystal , condensed matter physics , coulomb , crystal (programming language) , variable range hopping , fermi level , density of states , acceptor , physics , impurity , electron , quantum mechanics , thermal conduction , computer science , programming language
It is shown that pinning of the electron Wigner crystal by a small concentration of charged impurities creates the finite density of charged localized states near the Fermi level. In the case of residual impurities in the spacer this density of states is related to nonlinear screening of a close acceptor by a Wigner crystal vacancy. On the other hand, intentional doping by a remote layer of donors is a source of a long range potential, which generates dislocations in Wigner crystal. Dislocations in turn create charged localized states near the Fermi level. In both cases Coulomb interaction of localized states leads to the soft Coulomb gap and ES variable range hopping at low enough temperatures. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)