Spectacular decrease of the melting magnetic field in the charge-ordered state of Pr0.5Ca0.5MnO3 films under tensile strain

An insulator-to-metal transition below 240 K is induced by applying a 7 T m agnetic field in Pr0.5Ca0.5MnO3 thin films grown by the pulsed laser deposi tion technique on [100]-SrTiO3 substrates. This value of the melting magnet ic field, much lower that the one required in bulk (similar to 20 T), is as sumed to be an effect of the tensile stress. These results confirm the impo rtance of the bandwidth in the control of the physical properties of this c ompound and open the route to get colossal magnetoresistive properties by u sing strain effects. (C) 2000 American Institute of Physics. [S0003-6951(00 )01033-0].