Article

Modification of the ground state in Sm-Sr manganites by oxygen isotope substitution

University of Groningen, Groningen, Groningen, Netherlands
Physical review. B, Condensed matter (Impact Factor: 3.66). 09/2002; 67(10). DOI: 10.1103/PhysRevB.67.100410
Source: arXiv

ABSTRACT

The effect of $^{16}$O $\to$ $^{18}$O isotope substitution on electrical resistivity and magnetic susceptibility of Sm$_{1-x}$Sr$_x$MnO$_3$ manganites is analyzed. It is shown that the oxygen isotope substitution drastically affects the phase diagram at the crossover region between the ferromagnetic metal state and that of antiferromagnetic insulator (0.4 $< x <$ 0.6), and induces the metal-insulator transition at for $x$ = 0.475 and 0.5. The nature of antiferromagnetic insulator phase is discussed. Comment: 4 pages, 3 eps figures, RevTeX, submitted to Phys. Rev. Lett

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