Single-laser polarization-controlled optical sampling system for THz-TDS

We demonstrate a polarization-multiplexed, single-laser system for terahertz (THz) time-domain spectroscopy without an external delay line. The fiber laser emits two pulse trains with independently adjustable repetition rates, utilizing only one laser-active section and one pump diode. With a standard fiber-coupled THz setup and an optical amplifier stage, we are able to measure transients with a spectral bandwidth of 2.5 THz and a dynamic range of 50 dB in a measurement time of 1s with a timing accuracy of the THz pulse of approximately 50 fs. Based on the novel laser architecture, we call this new approach single-laser polarization-controlled optical sampling, or SLAPCOPS.