Inelastic light scattering from magnetic fluctuations in CuGeO3

Magnetic fluctuations in CuGeO3 are studied using inelastic light scattering experiments over a broad temperature range. In the dimerized phase (T < 14 K), scattering resulting from maxima in the magnonlike density of states and from spin-phonon coupled modes are reported. In the short-range order regime of the uniform phase (14 < T < 60 K) the results confirm the existence of a spin-wave continuum, as expected for a one-dimensional quantum Heisenberg chain. At high temperatures (T > 60 K) clear evidence is given for the existence of low-dimensional diffusive fluctuations.