The measurements of carrier density and mobility in magnetised materials by the help of helicon maser

Abstract

A new measurement method of the carrier density and mobility in metals and semiconductors by the help of magnetoplasmic helicon waves in magnetised solid-state plasma is proposed. The helicons in this case are excited by radio frequencies f1 (the range 100 – 600 MHz) much higher than the helicon resonator frequency f2 (the range of 20 MHz). From the frequency f2 and the resonance bandwidth the carrier density and mobility may be obtained. It is expedient to call such a device a sort of helicon maser and a high radio frequency electromagnetic field the pumping field. In full analogy with maser (o laser) the semiconductor sample plays a role of the active material and the cable line – of the resonator. In the experimental device the semiconductor n- InSb was used for the active material. The constant magnetic field varied within the interval 0-23 T.