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Structural phase transitions and sound velocity anomalies in La(1-x)Sr(x)MnO3

Yu. P. Gaidukov·N. P. Danilova·N. A. Vassilieva·A. M. Balbashov
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Abstract

The sound velocities dependencies on temperature V(T) were measured by means of resonance method have on the thin plates of quasimonocrystalline manganites La(1-x)Sr(x)MnO3. Results are presented for x=0.1, 0.125, 0.15, 0.175 and 0.2 in the temperature range from 70 to 350K. The V(T) behavior correlates with those of susceptibilities and magnetic moment M(T). For x=0.175 and 0.2 the transition to ferromagnetic state is accompanied by appearance of large but smooth rise in V(T) whereas structural phase transition between the rhomboedral (R) and orthorhombic (O) structures is accompanied by sharp increase up to 15-20% in V(T). For x=0.1, 0.125 and 0.15 the structural phase transition between Jahn-Teller distorted orthorhombic structure (O') and pseudocubic one (O'') is accompanied by deep minimum (~20-30%) in V(T).

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Yu. P. Gaidukov, N. P. Danilova, N. A. Vassilieva, A. M. Balbashov. 1999-07-23. Structural phase transitions and sound velocity anomalies in La(1-x)Sr(x)MnO3. https://arxiv.org/abs/cond-mat/9907361

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