Measurement of the bandwidth of Helicon Maser

Abstract

Radio frequency (RF) magnetoplasmic waves known as helicons will propagate in solid-state plasmas of metals and semiconductors when a strong magnetic field is applied. In Helicon Maser (HM) the helicons are exited by RFs much higher than the helicon generation frequency. The higher frequency e/m field may be called a pumping field. In analogy with the usual maser (or laser) the magnetized semiconductor sample plays the role of active material and the connecting cable - the role of high quality external resonator. THe bandwidth of HM is much narrower than in case of isolated sample (the same situation as in case of laser). The new method of HM bandwidth measurement is considered. InSb and Ge were used for active materials. The constant magnetic field varied within ihe interval 0-23 Tesla.