Experimental realization of Helicon Maser in magnetized solid-state plasma

Abstract

Radio frequency (RF) magnetoplasmic waves known as helicons will propagate in solid-state plasmas when a strong magnetic field is applied. In our device for the first time the helicons were excited by RFs (the range 100–2000 MHz) much higher than the helicon generation frequency (the main peak at 20 MHz). It is expedient to call this experimental device a Helicon Maser (HM) and the higher frequency field–a pumping field. In full analogy with the usual maser (or laser) the 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 the bandwidth of isolated sample (exactly the same situation as in case of laser). In the experimental device the n-InSb was used for the active material. The constant magnetic field varied within the interval 0–23 T.