| Full text | |
| Author(s): |
Renosto, S. T.
[1]
;
Lang, R.
[2]
;
Diez, E.
[1]
;
Correa, L. E.
[3]
;
da Luz, M. S.
[4]
;
Fisk, Z.
[5]
;
Machado, A. J. S.
[3]
Total Authors: 7
|
| Affiliation: | [1] Univ Salamanca, Dept Fis Fundamental, Nanolab, Grp Nanotecnol, E-37008 Salamanca - Spain
[2] Univ Fed Sao Paulo, Inst Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos - Brazil
[3] Univ Sao Paulo, Dept Mat, BR-12602810 Lorena - Brazil
[4] Univ Fed Triangulo Mineiro, BR-38066200 Uberaba - Brazil
[5] Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 - USA
Total Affiliations: 5
|
| Document type: | Journal article |
| Source: | Journal of Alloys and Compounds; v. 787, p. 414-422, MAY 30 2019. |
| Web of Science Citations: | 1 |
| Abstract | |
In this paper, a comprehensive study of the effects of Ni-doping on structural, electrical, thermal and magnetic properties of the NbB2 is presented. Low amounts (<= 10%) of Ni substitution on Nb sites cause structural distortions and induce drastic changes in the physical properties, such as the emergence of a bulk superconducting state with anomalous behaviors in the critical fields (lower and upper) and in the specific heat. Ni-doping at the 9 at.% level, for instance, is able to increase the critical temperature (T-c) in stoichiometric NbB2 (<1.3 K) to approximately 6.0 K. Bulk superconductivity is confirmed by magnetization, electronic transport, and specific heat measurements. Both H-c1 and H-c2 critical fields exhibit a linear dependence with reduced temperature (T/T-c), and the specific heat deviates remarkably from the conventional exponential temperature dependence of the single-band BCS theory. These findings suggest multiband superconductivity in the composition range from 0.01 <= x <= 0.10 (Nb1-xNixB2). (C) 2019 Elsevier B.V. All rights reserved. (AU) | |
| FAPESP's process: | 18/08819-2 - Growth of single crystals of CdI2 prototype dicalcogens and investigation of superconducting properties |
| Grantee: | Lucas Eduardo Corrêa |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 14/25235-3 - Study of the Defect Structure and its Influence on the Phononic and Electronic Properties in M1-xVxB2 Superconducting Compounds |
| Grantee: | Sérgio Tuan Renosto |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |