Carrier-envelope offset frequency linewidth narrowing in a Cr:forsterite laser-based frequency comb

摘要

Cr:forsterite laser-based frequency combs are useful for spectroscopic purposes in the near-IR wavelength region. However, self-referenced Cr: forsterite combs tend to exhibit wide carrier-envelope offset frequency (f(0)) linewidths, which result in broad comb teeth. This can be attributed to significant frequency noise across the comb's spectral bandwidth. We have stabilized a prism-based Cr: forsterite laser comb and observed narrowing of the f(0) linewidth from similar to 1.4 MHz down to similar to 100 kHz by changing only the prism insertion, and to 23 kHz by inserting a knife edge into the intracavity beam while keeping the same prism insertion. The noise dynamics of the Cr: forsterite laser frequency comb are investigated with the goal of explaining this f(0) narrowing phenomenon. (C) 2016 Optical Society of America