An inorganic spin-Peierls compound CuGeO3 has been studied by high-field ESR combining pulsed magnetic fields and far-infrared lasers. In EPR measurements under megagauss fields, an exchange splitting is observed and the interchain exchange coupling is evaluated. In the dimerized spin-Peierls phase, a direct transition between the singlet ground and the triplet excited states is observed. This result supports the existence of the second gap between the triplet state and the continuum. Collective spin wave modes in the field-induced magnetic phase and in the antiferromagnetic phase of the impurity-doped system have been also studied.
- Electron spin resonance
- Magnetic excitation