A control system has been developed for automated amplitude scanning of spatial interference patterns using a dynamic plasmonic Michelson interferometer for experiments with terahertz radiation from the Novosibirsk Free Electron Laser (NovoFEL). The system automates investigations by controlling a group of optical positioners while simultaneously acquiring signals from photoelectric receivers and collecting and storing data with subsequent postprocessing. The system core consists of a personal computer running Python software. Optical signals processed by lock-in amplifiers are digitized using a custom-designed dual-channel analog-to-digital converter (ADC). The system provides automated data storage in Excel format for further analysis. Testing of the complex for measuring surface plasmon polariton characteristics at the NovoFEL wavelength of 141 μm showed good agreement with data obtained previously without this system.
Krasnopevtsev et al. (Mon,) studied this question.