Low phase noise THz generation from a fiber-referenced Kerr microresonator soliton comb.

THz oscillators generated via frequency-multiplication of microwaves are facing difficulty in achieving low phase noise. Photonics-based techniques, in which optical two tones are translated to a THz wave through opto-electronic conversion, are promising if the relative phase noise between the two tones is well suppressed. Here, a THz (≈560 GHz) wave with a low phase noise is provided by a frequency-stabilized, dissipative Kerr microresonator soliton comb. The repetition frequency of the comb is stabilized to a long fiber in a two-wavelength delayed self-heterodyne interferometer, significantly reducing the phase noise of the THz wave. A measurement technique to characterize the phase noise of the THz wave beyond the limit of a frequency-multiplied microwave is also demonstrated, showing the superior phase noise of the THz wave to any other photonic THz oscillators (>300 GHz). Low phase-noise THz wave generation is in high demand for applications such as wireless communications and radars. Here, the authors generate low-noise THz waves via photodetection of the carrier of a Kerr frequency comb, which is repetition-rate stabilized using a two-wavelength delayed self-heterodyne interferometer. [ABSTRACT FROM AUTHOR]