Terahertz-time domain spectroscopic measurement of moderately-doped silicon using InAs emitter under magnetic field

The complex refractive index of silicon using terahertz-time domain spectro scopy (THz-TDS), with an InAs wafer under the influence of a magnetic field as emitter, has been studied. By applying a magnetic field on the InAs emi tter, the detected temporal waveform broadens and the spectral weight of it s Fourier spectrum shifts toward the low frequency region. Calculating the real in) and imaginary (K) parts of the complex refractive index of silicon , it is found that with the application of a magnetic held the plots of the se quantities in the low frequency region (sub-terahertz region) are smooth er than those without magnetic field. These features indicate that a signif icant enhancement of the signal-to-noise (SIN) ratio in the low frequency r egion can be obtained by applying a magnetic field on the InAs emitter.