JSAP Spring / Autumn Meeting

The lock-in detection enables measurement of a signal on high background with high signal to noise ratio (SNR) relying on a bandwidth limiting at the lock-in frequency. It also enables evaluation of response lag according to the phase retardation. However, the obtained value is a data at merely the lock-in frequency. We developed a time division lock-in detection method to observe response waveform in the time domain. The signal is divided in the period of a perturbation on the sample, and each divided signal is lock-in detected. This method enables direct observation of the waveform of response lad in the time domain as well as the enhancement of SNR with the bandwidth limiting.