The spin-wave excitation mode from the spin-polarized ground state in the fractional quantum Hall system at the Landau level filling of $\nu =\frac{1}{\mathrm{}(2m+1)\mathrm{}}$ is shown, by comparing with the exact numerical result for finite systems, to be accurately described, for wavelengths exceeding the magnetic length, in terms of the composite-fermion picture for the spin-wave (magnon) theory formulated in the spherical geometry. This indicates that the composite-fermion approach extends to excited states and also provides the spin stiffness in terms of exchange interaction with transformed interparticle interactions.

• Received 3 May 1994

DOI:https://doi.org/10.1103/PhysRevLett.73.3568