Electron-hopping modes in NiMn_(2)O_(4+δ) materials

The resistance versus temperature (R–T) characteristics of NiMn_(2)O_(4+δ) thermistors have been analyzed. In the literature, electron transport in manganate spinels is commonly described by a small-polaron model for nearest neighbor hopping, but variable range hopping (VRH) has not been considered...

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Bibliographic Details
Authors: Schmidt, Rainer, Basu, A., Brinkman, A. W., Klusek, Z., Datta, P. K.
Format: article
Publication Date:2005
Country:España
Institution:Universidad Complutense de Madrid (UCM)
Repository:Docta Complutense
Language:English
OAI Identifier:oai:docta.ucm.es:20.500.14352/51564
Online Access:https://hdl.handle.net/20.500.14352/51564
Access Level:Open access
Keyword:537
Conductivity
Thermistors.
Electricidad
Electrónica (Física)
2202.03 Electricidad
Description
Summary:The resistance versus temperature (R–T) characteristics of NiMn_(2)O_(4+δ) thermistors have been analyzed. In the literature, electron transport in manganate spinels is commonly described by a small-polaron model for nearest neighbor hopping, but variable range hopping (VRH) has not been considered so far. In this study differentiated R–T data were analyzed, allowing a clear distinction between different modes of hopping. In pressed pellets and thick screen printed films conduction was well described by a VRH model for a parabolic density of states, which was confirmed by scanning tunneling spectroscopy.