Optical and electronic properties of doped silicon from 0.1 to 2 THz

Using a source of freely propagating subpicosecond pulses of THz radiation, we have measured the absorption and dispersion of both N- and P-type, 1 Ω cm silicon from 0.1 to 2 THz. These results give the corresponding frequency-dependent complex conductance over the widest frequency range to date. The data provide a complete view on the dynamics of both electrons and holes and are well fit by the simple Drude relationship.