Original scientific paper
Magnetic-field induced hopping conduction of a pseudo-gap interacting system
Debnarayan Jana
; Department of Physics, University College of Science and Technology, 92 A. P. C. Road, Kolkata 700 009, W.B., India
Abstract
We present a simple scaling form of Mott conductivity formula in case of amorphous material in presence of an external magnetic field in an arbitrary spatial dimension d. The model of the interacting system is chosen as the variable range hopping (VRH) one with density of states having a soft gap at the Fermi energy. We indicate the relation between the conductivity exponents (both in weak and strong magnetic field) with that without the magnetic field. The exponents related to the variation of activation energy with temperature have also been computed. We also indicate the lower as well as the upper bound of the conductivity exponents. Besides, a connecting formula between the exponents (non-interacting, interacting with weak magnetic field and interacting with strong magnetic field) shows that only two of them are independent. Previously-known results can be obtained from this generalized form of the conductivity. Finally, a comparison of the exponents has been done with the strong electric field case.
Keywords
variable range hopping (VRH) conduction; pseudo-gap amorphous material
Hrčak ID:
302738
URI
Publication date:
2.5.2010.
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