ON THE POSSIBILITY OF OBSERVATION AND THE INTENSITY OF (NN') AND (NN) TRANSITIONS BETWEEN EXCITON-STATES IN CU2O

The investigation of spectra from the creation of excitons has yielded significant information. In particular, in good crystals of Cu//2O, as many as 9 exciton states are observed in the 'yellow series'. An entirely different kind of spectra has barely been observed till now, but should be observable with laser excitation. These spectra concern transitions between states of the same exciton (n yields n prime ) transitions. These spectra should be observed in the IR if the concentration of N of excitons in a state n is sufficiently high. This has become possible with laser excitation. The aim of this work is to show that such transitions could give important information and should have appreciable oscillator strengths, comparable to atomic transitions.