Effect of Ultrafast Thermal Quenching on the Transport and Magnetotransport Properties of Nd_(0.67)Sr_(0.33)MnO_3

摘要

We report on the results of ultrafast quenching of Nd_(1-x)Sr_xMnO_3 (x = 0.33) from 1200 ℃ down to -196 ℃ in a fraction of a second, at ambient pressure. Transport measurements showed a 27 K shift in the metal-insulator transition (MIT) temperature of the quenched sample compared to the as-grown sample. We found that ultrafast quenching significantly widens the temperature range of the magnetoresistance (MR) from few degrees to over 200 K. These changes are attributed to induced stress and change in grain size, which X-Ray analysis and SEM measurement have confirmed. X-Ray measurements confirms the presence of single phase in both the slowly-cooled and ultrafast-cooled samples.