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Title: Role of interband scattering in neutron irradiated MgB{sub 2} thin films by scanning tunneling spectroscopy measurements

Abstract

A series of MgB{sub 2} thin films systematically disordered by neutron irradiation have been studied by scanning tunneling spectroscopy. The c-axis orientation of the films allowed a reliable determination of the local density of states of the {pi} band. With increasing disorder, the conductance peak moves towards higher voltages and becomes lower and broader, indicating a monotonic increase of the {pi} gap and of the broadening parameter. These results are discussed in the framework of two-band superconductivity.

Authors:
; ;  [1];  [2]; ;  [3];  [3];  [4];  [5];  [6];  [5]
  1. University of Napoli and CNR/INFM-Coherentia, Via Cinthia, I-80126 Naples (Italy)
  2. Paul Scherrer Institut, CH-5232 Villigen (Switzerland)
  3. CNR/INFM-LAMIA, Via Dodecaneso 33, I-16146 Genova (Italy)
  4. (United States)
  5. Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
  6. (Saudi Arabia) (Italy)
Publication Date:
OSTI Identifier:
20976641
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevB.75.014515; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DENSITY; ELECTRIC POTENTIAL; ENERGY GAP; IRRADIATION; MAGNESIUM BORIDES; NEUTRONS; SCANNING TUNNELING MICROSCOPY; SCATTERING; SPECTROSCOPY; SUPERCONDUCTIVITY; THIN FILMS; TUNNEL EFFECT; TYPE-II SUPERCONDUCTORS

Citation Formats

Di Capua, R., Salluzzo, M., Vaglio, R., Aebersold, H. U., Ferdeghini, C., Putti, M., Ferrando, V., Pennsylvania State University, University Park, Pennsylvania 16802, Orgiani, P., CNR/INFM-SUPERMAT, I-84081 Baronissi, and Xi, X. X. Role of interband scattering in neutron irradiated MgB{sub 2} thin films by scanning tunneling spectroscopy measurements. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.014515.
Di Capua, R., Salluzzo, M., Vaglio, R., Aebersold, H. U., Ferdeghini, C., Putti, M., Ferrando, V., Pennsylvania State University, University Park, Pennsylvania 16802, Orgiani, P., CNR/INFM-SUPERMAT, I-84081 Baronissi, & Xi, X. X. Role of interband scattering in neutron irradiated MgB{sub 2} thin films by scanning tunneling spectroscopy measurements. United States. doi:10.1103/PHYSREVB.75.014515.
Di Capua, R., Salluzzo, M., Vaglio, R., Aebersold, H. U., Ferdeghini, C., Putti, M., Ferrando, V., Pennsylvania State University, University Park, Pennsylvania 16802, Orgiani, P., CNR/INFM-SUPERMAT, I-84081 Baronissi, and Xi, X. X. Mon . "Role of interband scattering in neutron irradiated MgB{sub 2} thin films by scanning tunneling spectroscopy measurements". United States. doi:10.1103/PHYSREVB.75.014515.
@article{osti_20976641,
title = {Role of interband scattering in neutron irradiated MgB{sub 2} thin films by scanning tunneling spectroscopy measurements},
author = {Di Capua, R. and Salluzzo, M. and Vaglio, R. and Aebersold, H. U. and Ferdeghini, C. and Putti, M. and Ferrando, V. and Pennsylvania State University, University Park, Pennsylvania 16802 and Orgiani, P. and CNR/INFM-SUPERMAT, I-84081 Baronissi and Xi, X. X.},
abstractNote = {A series of MgB{sub 2} thin films systematically disordered by neutron irradiation have been studied by scanning tunneling spectroscopy. The c-axis orientation of the films allowed a reliable determination of the local density of states of the {pi} band. With increasing disorder, the conductance peak moves towards higher voltages and becomes lower and broader, indicating a monotonic increase of the {pi} gap and of the broadening parameter. These results are discussed in the framework of two-band superconductivity.},
doi = {10.1103/PHYSREVB.75.014515},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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  • Cryogenic scanning tunneling microscopy and magnetization measurements were used to study the superconducting properties of MgB{sub 2}. The magnetization measurements show a sharp superconductor transition at T{sub c}=39 K, in agreement with previous works. The tunneling spectra exhibit BCS-like gap structures, with gap parameters in the range of 5 to 7 meV, yielding a ratio of 2{Delta}/k{sub B}T{sub c}{similar_to}3{minus}4. This suggests that MgB{sub 2} is a conventional BCS s-wave superconductor, either in the weak-coupling or in the {open_quotes}intermediate-coupling{close_quotes} regime.
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