Effect Of Mn Substitution On The Thermo-Power Of The Superconductor Mg1-Xmnxb2

In this communication a systematic study has been made on the effect of Mn substitution on the thermo-power of MgB2 superconducting compounds involving 0%, 0.5%, 1.0%, 1.5% and 2% Mn content. The superconducting transition has been found to be very sharp for the pure compound of MgB2 and it is observed that the transition width increases with Mn content. For small values of Mn content, the thermo-power S(T) increases with Mn content which suggests that the hole density increases. However, with further increase in Mn content, a small decrease in S(T) is observed. For all the compounds, we have observed the expected linear region at low temperatures. There is no systematic trend in the slopes dS/dT with Mn content.