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Low-temperature specific heat of La0.78Pb0.22MnO3-d manganite

L. Ghivelder·R. S. Freitas·R. E. Rapp·F. A. B. Chaves·M. Gospodinov·M. A. Gusmao
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Abstract

The specific heat of the perovskite manganite La0.78Pb0.22MnO3-d was measured from 0.5 to 25 K. The results yield values of the electronic density of states, the Debye temperature, and the spin-wave stiffness constant of the compound. The magnetic contribution was found to be consistent with the existence of a gap in the spin-wave spectrum, and a phonon term in T^5 was needed to fit the data.

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L. Ghivelder, R. S. Freitas, R. E. Rapp, F. A. B. Chaves, M. Gospodinov, M. A. Gusmao. 2000-05-14. Low-temperature specific heat of La0.78Pb0.22MnO3-d manganite. https://doi.org/10.1016/s0304-8853(00)01026-x

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