Magnetotransport and the upper critical magnetic field in MgB2

P. Szabó; P. Samuely; A. G.M. Jansen; T. Klein; J. Marcus; D. Fruchart; S. Miraglia

doi:10.1016/S0921-4534(01)01252-7

Magnetotransport and the upper critical magnetic field in MgB₂

P. Szabó, P. Samuely, A. G.M. Jansen, T. Klein, J. Marcus, D. Fruchart, S. Miraglia

Research output: Contribution to journal › Article › peer-review

Abstract

Magnetotransport measurements are presented on polycrystalline MgB₂ samples. The 'resistive' upper critical magnetic field reveals a temperature dependence with a positive curvature from T_c = 39.3 K down to about 20 K, then changes to a slightly negative curvature reaching 25 T at 1.5 K. The 25-T upper critical field is much higher than what is known so far on polycrystals of MgB₂ but it is in agreement with recent data obtained on epitaxial MgB₂ films. The deviation of B_c2(T) from standard BCS might be due to the proposed two-gap superconductivity in this compound. The observed quadratic normal-state magnetoresistance with validity of Kohler's rule can be ascribed to classical trajectory effects in the low-field limit.

Original language	English
Pages (from-to)	250-253
Number of pages	4
Journal	Physica C: Superconductivity and its Applications
Volume	369
Issue number	1-4
DOIs	https://doi.org/10.1016/S0921-4534(01)01252-7
Publication status	Published - 15 Mar 2002
Externally published	Yes

Keywords

Exotic superconductors
Magnetotransport
Upper critical magnetic field

Access to Document

10.1016/S0921-4534(01)01252-7

Cite this

@article{f826c34d69764bf6a056266783ba6e8d,

title = "Magnetotransport and the upper critical magnetic field in MgB2",

abstract = "Magnetotransport measurements are presented on polycrystalline MgB2 samples. The 'resistive' upper critical magnetic field reveals a temperature dependence with a positive curvature from Tc = 39.3 K down to about 20 K, then changes to a slightly negative curvature reaching 25 T at 1.5 K. The 25-T upper critical field is much higher than what is known so far on polycrystals of MgB2 but it is in agreement with recent data obtained on epitaxial MgB2 films. The deviation of Bc2(T) from standard BCS might be due to the proposed two-gap superconductivity in this compound. The observed quadratic normal-state magnetoresistance with validity of Kohler's rule can be ascribed to classical trajectory effects in the low-field limit.",

keywords = "Exotic superconductors, Magnetotransport, Upper critical magnetic field",

author = "P. Szab{\'o} and P. Samuely and Jansen, \{A. G.M.\} and T. Klein and J. Marcus and D. Fruchart and S. Miraglia",

year = "2002",

month = mar,

day = "15",

doi = "10.1016/S0921-4534(01)01252-7",

language = "English",

volume = "369",

pages = "250--253",

journal = "Physica C: Superconductivity and its Applications",

issn = "0921-4534",

number = "1-4",

}

TY - JOUR

T1 - Magnetotransport and the upper critical magnetic field in MgB2

AU - Szabó, P.

AU - Samuely, P.

AU - Jansen, A. G.M.

AU - Klein, T.

AU - Marcus, J.

AU - Fruchart, D.

AU - Miraglia, S.

PY - 2002/3/15

Y1 - 2002/3/15

N2 - Magnetotransport measurements are presented on polycrystalline MgB2 samples. The 'resistive' upper critical magnetic field reveals a temperature dependence with a positive curvature from Tc = 39.3 K down to about 20 K, then changes to a slightly negative curvature reaching 25 T at 1.5 K. The 25-T upper critical field is much higher than what is known so far on polycrystals of MgB2 but it is in agreement with recent data obtained on epitaxial MgB2 films. The deviation of Bc2(T) from standard BCS might be due to the proposed two-gap superconductivity in this compound. The observed quadratic normal-state magnetoresistance with validity of Kohler's rule can be ascribed to classical trajectory effects in the low-field limit.

AB - Magnetotransport measurements are presented on polycrystalline MgB2 samples. The 'resistive' upper critical magnetic field reveals a temperature dependence with a positive curvature from Tc = 39.3 K down to about 20 K, then changes to a slightly negative curvature reaching 25 T at 1.5 K. The 25-T upper critical field is much higher than what is known so far on polycrystals of MgB2 but it is in agreement with recent data obtained on epitaxial MgB2 films. The deviation of Bc2(T) from standard BCS might be due to the proposed two-gap superconductivity in this compound. The observed quadratic normal-state magnetoresistance with validity of Kohler's rule can be ascribed to classical trajectory effects in the low-field limit.

KW - Exotic superconductors

KW - Magnetotransport

KW - Upper critical magnetic field

U2 - 10.1016/S0921-4534(01)01252-7

DO - 10.1016/S0921-4534(01)01252-7

M3 - Article

AN - SCOPUS:0037086924

SN - 0921-4534

VL - 369

SP - 250

EP - 253

JO - Physica C: Superconductivity and its Applications

JF - Physica C: Superconductivity and its Applications

IS - 1-4