Pressure Dependence of the Superconducting Transition Temperature of Magnesium Diboride
M. Monteverde,1
M. Núñez-Regueiro,1*
N. Rogado,2
K. A. Regan,2
M. A. Hayward,2
T. He,2
S. M. Loureiro,2
R. J. Cava2
We studied the pressure and temperature dependence of the
electrical resistivity of the superconducting compound magnesium diboride (MgB2). The superconducting transition
temperature decreases monotonically with pressure, being parabolic or
linear, depending on samples. The rate of decrease under pressure is
higher than in conventional superconductors. We discuss our results in
terms of the semimetallic character of the electronic band structure of
MgB2.
1 Centre de Recherches sur les Très
Basses Températures, CNRS, BP166 Cedex 09, 38042 Grenoble,
France.
2 Department of Chemistry and Materials
Institute, Princeton University, Princeton, NJ 08544, USA.
*
To whom correspondence should be addressed. E-mail:
nunez{at}polycnrs-gre.fr