Observation of new type resonances in double resonance experiment

Jean Pierre Vigier

B P Kibble, George William Series

Abstract This is an investigation, at low frequencies, of the modulation of fluorescent light which has already been found a t higher frequencies in a double resonance experiment. In the earlier work, in which the frequency of magnetic resonance was of order 10 Mc/s, the Zeeman levels of the excited atom s were well separated compared with their natural width (1 M c/s): in the present work they are completely unresolved at the centre of the magnetic resonance, which is studied a t 1 kc/s. The principal resonance phenomena are observed as before under the new conditions: they are centred on a field near to zero, while their width is greater than 1G. New resonance phenomena are also studied, which do not appear when the resonance frequency is greater than the natural width of the levels. A theory, previously published, is applied to predict the form of the new resonance curves. An identical result is predicted by the use of a classical model.

Alan Corney

Noriaki Tsukada, T. Yabuzaki, Toru Ogawa

A theoretical and experimental study has been made of the effect of transverse optical pumping in the optical-rf double resonance of cesium atoms. The solution of Bloch type equations shows that the Hanle effect and new type resonances become notable in the weak magnetic field or for strong rf field, as the effect of the transverse pumping. The new type resonances appear in the unmodulated component and the components modulated at the first and the second harmonics of the applied rf frequency in the pumping light beam transmitted through the sample cell. It is predicted that the new type resonances are not only shifted but also broadened as the intensity of rf field increases. The shift, broadening and the intensity for observed new type resonances are in good agreement with the theoretical prediction.

J. I. Steinfeld, Paul L. Houston

Wolfgang Ernst, Thoms Törring

We have demonstrated a new kind of microwave-optical double-resonance experiment monitoring the nonlinear interaction between microwave radiation and a laser beam via changes in light polarization. Compared with conventional microwave-optical double-resonance experiments signals are observed at considerably lower laser power density and with greatly improved resolution.