Spin–lattice interaction in colossal magnetoresistance manganites

The metal–insulator transition and underlying spin dynamics in La0.7D0.3MnO3 (D=Ca, Sr) are investigated using optical pump–probe spectroscopy at 1.5 eV. Our measurements, which span the ferromagnetic–paramagnetic transition temperature, reveal that the dynamics of the optically induced spectral weight transfer follow the temperature dependence of the magnetic specific heat. This dependence reflects the intrinsic interdependence between the optical conductivity and magnetism in the manganites allowing for the determination of the spin-lattice coupling magnitude.

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