Advanced techniques for terahertz detection using spectral-domain interferometry

We demonstrate and compare the use of Mach-Zehnder and the fiber based interferometer schemes in improving the performance of terahertz electric field measurements based on spectral-domain interferometry. The new schemes enable unlimited temporal scanning window without significant loss in the signal-to-noise ratio, thus overcoming a major limitation in conventional spectral-domain interferometry techniques for terahertz electric field detection. Moreover, both detection techniques offer significantly higher dynamic range compared to the conventional electro-optic sampling technique.