Terahertz response of long-lived photoexcited electrons in silicon observed using single-shot terahertz spectroscopy

We observed the Drude response of photoexcited electrons in high resistivity silicon by using single-shot terahertz spectroscopy. In contrast to conventional optical-pump and terahertz-probe spectroscopy, this technique can significantly reduce the measurement time and repetition rate of pump pulses. As a result, the dynamics of long-lived photoexcited carriers in silicon is clearly observed without a pileup of the carriers.