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Spin wave measurements have been carried out in ferromagnetic (F) La(1-x)(Sr,Ca)(x)MnO(3) with x(Sr) = 0.15, 0.175, 0.2, 0.3, and x(Ca) = 0.3. In all q directions, close to the zone boundary, the spin wave spectra consist of several energy levels, with the same values in the metallic and the x approximately 1/8 doping ranges. For x(Sr) = 0.15, the data are quantitatively interpreted in terms of quantized spin waves within 2D ordered F domains or clusters of 4a size. The same picture holds in the metallic state with, however, disordered clusters embedded in a 3D F matrix.

We report a study of spin waves in ferromagnetic La1-xCaxMnO3, at concentrations x=0.17 and x=0.2 very close to the metallic transition (x=0.225). Below T(C), in the quasimetallic state (T=150 K), nearly q-independent energy levels are observed. They are characteristic of standing spin waves confined into finite-size ferromagnetic domains, defined only in the (a,b) plane for x=0.17, and in all directions for x=0.2. They allow an estimation of the domain's size, a few lattice spacings, and of the magnetic coupling constants inside the domains. These constants, anisotropic, are typical of an orbital-ordered state, allowing one to characterize the domains as "hole poor." The precursor state of the collossal magnetoresistance metallic phase appears, therefore, as an assembly of small orbital-ordered domains.