R e p le 20 juillet 1989Les jonctions polaristes prksentent une susceptibilitt Clectrique vis-a-vis d'un champ radiofrkquence E. Ceci s'observe quand E est parallkle a la jonction, ainsi que nous I'avons deji rapport6 anterieurement, mais aussi, quand les circonstances exptrimentales le permettent, lorsque E est perpendiculaire a cette jonction. De plus, un champ magnttique modifie de faqon significative les phtnomknes observes. On peut ainsi prkciser la structure du champ local hyperfrtquence.Polarized junctions show an electric susceptibility toward a radiofrequency field E when it is parallel to the metallurgic plane of the junction, but also, in some circumstances, when E is perpendicular to the junction. Furthermore, a magnetic field modifies significantly the observed phenomena. The experiments give structural information about the local field.

No abstract

When an alternating electric field is applied parallel to a junction, the radiofrequency susceptibility gives an absorption having a maximum versus the direct current polarization of the junction; the real part of the susceptibility is negative. The explanation of both features involves an internal field parallel to the alternating field. The experiment allows the measurement of the concentration of minority carriers.

Recu le 21 juillet 1988Les effets de susceptibilitC Clectrique transverse radiofrtquence d'une jonction polarisCe se manifestent lors de mesures en cavitC microonde. On peut rechercher s'il se produit des effets sur l'indice des matiriaux, ce qui fait I'objet de la p:esente Ctude ob nous examinons les variations d'indice microonde en propagation quasi-optique. On observe une diminution de la rkflectance, une augmentation de la transmittance, dues a la diminution de I'indice hertzien. Ceci est conforme a la thCorie proposCe prCcCdemment, qui tient compte d'un champ local microonde.In previous papers, we have studied the variations of radiofrequency susceptibility of a junction versus dc polarization. Here, we study the effect of variations of the refraction index on a microwave. An increase of the carrier concentration produces a diminution of the index, a decrease of reflected power, and an increase of transmitted power. This is in agreement with the theory, which takes into account the local microwave field.