Boron isotope effect in superconducting MgB2.
We report the preparation method of and boron isotope effect for MgB2, a new binary intermetallic superconductor with a remarkably high superconducting transition temperature T(c)(10B) = 40.2 K. Measurements of both temperature dependent magnetization and specific heat reveal a 1.0 K shift in T(c) between Mg11B2 and Mg10B2. Whereas such a high transition temperature might imply exotic coupling mechanisms, the boron isotope effect in MgB2 is consistent with the material being a phonon-mediated BCS superconductor.
Bud'ko
S L
SL
Ames Laboratory, Iowa State University, Ames, Iowa 50011, USA.
Lapertot
G
G
Petrovic
C
C
Cunningham
C E
CE
Anderson
N
N
Canfield
P C
PC