Fourier transform spectroscopy by repetition rate sweeping of a single electro-optic frequency comb

We demonstrate the operation of a Fourier transform spectrometer that operates by sweeping the pulse repetition frequency of an electro-optic frequency comb. Incorporating a length-imbalanced interferometer, this single-comb system is analogous to a conventional dual-comb system, but with a greatly simplified design. The functionality of the spectrometer is demonstrated via the high-resolution spectrum measurement of an H¹³C¹⁴N reference gas cell.