ac initial magnetic susceptibility, thermal expansion, and magnetostriction measurements were performed on a polycrystal of ${\mathrm{La}}_{0.60}{\mathrm{Y}}_{0.07}{\mathrm{Ca}}_{0.33}{\mathrm{MnO}}_3$ manganese oxide. We observed a spontaneous volume magnetic contribution ( $\cong 1\times {10}^{-3\mathrm{}}$ at $T_C=160\mathrm{}\pm 5\mathrm{K}$). This extra contribution sharply decreases at $T_C$ as a consequence of the metal ( $M$)–insulator ( $I$) transition, and is suppressed under an applied magnetic field. This shows that the transition to the $M$ state is induced by the field in the $I$ regime, producing strong magnetoelastic effects. The present results demonstrate the close relationship between magnetoelastic and magnetotransport properties in this compound.

• Received 12 May 1995

DOI:https://doi.org/10.1103/PhysRevLett.75.3541