Simultaneous measurements of resistance and elastic modulus in La2/3Ca1/3MnlO3

We have measured the anelastic constants of the magnetoresistant perovskite La2/3Ca1/3MnO3 around the metal-insulator transition in an inverted forced torsion pendulum (5 Hz) and by the vibrating reed technique (2 Khz). At torsion pendulum, the resistance of the sample was simultaneously measured during thermal cycles with and without applying a small magnetic field. The torsion and bending ("shear" and "Young" modulus) measurements were qualitatively similar. The modulus becomes harder at the transition while the internal friction value is greater in the vibrating reed experiment. There was no detected hysteresis cycling the temperature at 0.05 K/min around the transition temperature (260 K). But, if we applied a magnetic field of 320 Gauss an hysteresis of 0.7 K is observed which we suppose is related with the magnetic domains when the sample orders. There is a correlation between the resistance and torsion measurements which do not depend in the applied magnetic field.