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Raman scattering studies of spin, charge, and lattice dynamics in Ca_{2-x}Sr_{x}RuO_{4} (0 =< x < 0.2)

H. Rho·S. L. Cooper·S. Nakatsuji·H. Fukazawa·Y. Maeno
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Abstract

We use Raman scattering to study spin, charge, and lattice dynamics in various phases of Ca_{2-x}Sr_{x}RuO_{4}. With increasing substitution of Ca by Sr in the range 0 =< x < 0.2, we observe (1) evidence for an increase of the electron-phonon interaction strength, (2) an increased temperature-dependence of the two-magnon energy and linewidth in the antiferromagnetic insulating phase, and (3) evidence for charge gap development, and hysteresis associated with the structural phase change, both of which are indicative of a first-order metal-insulator transition (T_{MI}) and a coexistence of metallic and insulating components for T < T_{MI}.

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H. Rho, S. L. Cooper, S. Nakatsuji, H. Fukazawa, Y. Maeno. 2003-05-19. Raman scattering studies of spin, charge, and lattice dynamics in Ca_{2-x}Sr_{x}RuO_{4} (0 =< x < 0.2). https://doi.org/10.1103/physrevb.68.100404

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