Temperature dependence of resistivity and Hall-coefficient in a strongly disordered metal: NbN

Madhavi Chand; Archana Mishra; Y. M. Xiong; Anand Kamlapure; S. P. Chockalingam; John Jesudasan; Vivas Bagwe; Mintu Mondal; P. W. Adams; Vikram Tripathi; Pratap Raychaudhuri

doi:10.1103/physrevb.80.134514

arXiv · 0907.4735

Temperature dependence of resistivity and Hall-coefficient in a strongly disordered metal: NbN

Madhavi Chand·Archana Mishra·Y. M. Xiong·Anand Kamlapure·S. P. Chockalingam·John Jesudasan·Vivas Bagwe·Mintu Mondal·P. W. Adams·Vikram Tripathi·Pratap Raychaudhuri

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Abstract

We report the temperature dependence of resistivity (rho) and Hall coefficient (R_H) in the normal state of homogeneously disordered epitaxial NbN thin films with kFl~3.27-10.12. The superconducting transition temperature (Tc) of these films varies from 8.13K to 16.8K. While our least disordered film displays usual metallic behavior, for all the films with kFl<8.13, both and are negative up to 300K. We observe that R_H(T) varies linearly with rho(T) for all the films. Measurements performed on a 2nm thick Be film shows similar behavior >. This behavior is inconsistent with existing theories of localization and e-e interactions in a disordered metal.

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Madhavi Chand, Archana Mishra, Y. M. Xiong, Anand Kamlapure, S. P. Chockalingam, John Jesudasan, Vivas Bagwe, Mintu Mondal, P. W. Adams, Vikram Tripathi, Pratap Raychaudhuri. 2009-07-27. Temperature dependence of resistivity and Hall-coefficient in a strongly disordered metal: NbN. https://doi.org/10.1103/physrevb.80.134514

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