Increased Superconductivity for CNT Doped ${\hbox {MgB}}_{2}$ Sintered in 5T Pulsed Magnetic Field

The superconductivity of carbon nanotube (CNT) doped MgB
₂
sintered in pulsed magnetic field (PMF) was investigated with Raman scattering measurements and Raman spectral fit analysis. Although the carbon (C) substitution for the boron (B) is increased for the sample sintered in PMF, its superconductivity is advanced comparing with the sample sintered without PMF. The improved critical transition temperature, T
_c
, is attributed to the strengthening of the electron-phonon coupling (EPC) in MgB
₂
, as reflected by the broadened
E

_2g
mode in the Raman spectra, because the carbon atoms are homogeneously distributed in the boron planes.