Cyclotron resonance of electrons and of holes in cuprous oxide, Cu2O

The cyclotron resonance of electrons and of holes in Cu2O has been observed between 1.2 and 20K using frequencies of 34 and 137 GHz. Electrons have an isotropic polaron mass of (0.99+or-0.03)m0 where m0 is the mass of the free electron. Holes have isotropic polaron masses of (0.58+or-0.03)m0 and (0.69+or-0.04)m0, the error bars defining the points of half-height on the observed resonance curves. The authors attribute the electron resonance to the lowest Gamma 1+( Gamma 6+) minimum of the conduction band and the heavier hole to the uppermost Gamma 7+ hole band. The lighter hole is attributed tentatively to the Gamma 8+ maximum of the hole band. The exciton spectra of Cu2O are discussed in terms of these masses.