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Spin Dynamics of Double-Exchange Manganites with Magnetic Frustration

R. S. Fishman
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Abstract

This work examines the effects of magnetic frustration due to competing ferromagnetic and antiferromagnetic Heisenberg interactions on the spin dynamics of the double-exchange model. When the local moments are non-colinear, a charge-density wave forms because the electrons prefer to sit on lines of sites that are coupled ferromagnetically. With increasing hopping energy, the local spins become aligned and the average spin-wave stiffness increases. Phase separation is found only within a narrow range of hopping energies. Results of this work are applied to the field-induced jump in the spin-wave stiffness observed in the manganite Pr$_{1-x}$Ca$_x$MnO$_3$ with $0.3 \le x \le 0.4$.

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R. S. Fishman. 2004-02-12. Spin Dynamics of Double-Exchange Manganites with Magnetic Frustration. https://doi.org/10.1103/physrevb.70.012403

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