The Impact of Dispersion on Amplitude and Frequency Noise in a Yb-fiber Laser Comb

TL;DR

This paper investigates how net-cavity dispersion affects amplitude and frequency noise in a Yb-fiber laser comb, revealing that zero dispersion minimizes noise and enhances phase-locking capabilities.

Contribution

It provides the first detailed analysis of the relationship between net-cavity dispersion and noise characteristics in Yb-fiber laser combs, demonstrating the benefits of zero dispersion operation.

Findings

Zero net-cavity dispersion reduces f_CEO linewidth by ~100x.

Operating at zero dispersion lowers frequency noise spectral density.

Phase-locked f_CEO beat with low residual noise achieved at zero dispersion.

Abstract

We describe a Yb-fiber based laser comb, with a focus on the relationship between net-cavity dispersion and the frequency noise on the comb. While tuning the net cavity dispersion from anomalous to normal, we measure the amplitude noise (RIN), offset frequency (f_CEO) linewidth, and the resulting frequency noise spectrum on f_CEO. We find that the laser operating at zero net-cavity dispersion has many advantages, including an approximately 100x reduction in free-running f_CEO linewidth and frequency noise power spectral density between laser operation at normal and zero dispersion. In this latter regime, we demonstrate a phase-locked f_CEO beat with low residual noise.