Linewidth Study of Electric Dipole Induced Spin Resonance in Uniaxially Stressed n-InSb in Far Infrared Regions: Experimental

Abstract

We have carried out the linewidth measurements of the electric dipole induced spin resonance (EDSR) of conduction electrons in uniaxially stressed n-InSb in the far-infrared (FIR) regions. Our employed samples of n-InSb are highly doped with donors (6.0×10 15 cm -3 and 8.5×10 15 cm -3 ) and thus have metallic properties due to degenerate electrons. The linewidths of the EDSR have been obtained as the functions of the magnetic field (2.10∼6.39 T), the temperature (4.2∼70 K) and the donor concentration. The main features of the experimental results are the followings: (1) It is found that the minimum of the linewidth appears on the magnetic field dependence at 4.2 K. (2) In the lower resonance magnetic field (2.10 T and 2.74 T) and lower temperature regions ( T<∼20 K), we have recognized a slight reduction of the linewidth with the increasing of temperature. (3) For moderately high temperatures ( T>∼20 K), the increment of the linewidth is found on our employed experimental conditions for all samples. (4) For the sample with higher donor concentration, the enhancement of the linewidth is also found in comparison with the sample with lower donor concentration. In this paper, the linewidth of the EDSR spectrum is mainly discussed in respect of the experimental results. The detailed theoretical discussion will be presented in the following paper by Sugihara et al.