High-power ultrafast Yb:fiber laser frequency combs using commercially available components and basic fiber tools

TL;DR

This paper details the design and implementation of high-power ultrafast Yb:fiber laser frequency combs using commercially available parts, demonstrating their stability, tunability, and applications in spectroscopy and harmonic generation.

Contribution

It introduces practical, low-cost methods for constructing stable, high-power Yb:fiber laser frequency combs with new stabilization techniques and demonstrates their use in advanced scientific applications.

Findings

Achieved 9 W and 80 W power levels with stable ultrafast pulses.

Developed a new method for tuning the carrier-envelope offset frequency.

Demonstrated applications in femtosecond spectroscopy and high-order harmonic generation.

Abstract

We present a detailed description of the design, construction, and performance of high-power ultrafast Yb:fiber laser frequency combs in operation in our laboratory. We discuss two such laser systems: an 87 MHz, 9 W, 85 fs laser operating at 1060 nm and an 87 MHz, 80 W, 155 fs laser operating at 1035 nm. Both are constructed using low-cost, commercially available components, and can be assembled using only basic tools for cleaving and splicing single-mode fibers. We describe practical methods for achieving and characterizing low-noise single-pulse operation and long-term stability from Yb:fiber oscillators based on nonlinear polarization evolution. Stabilization of the combs using a variety of transducers, including a new method for tuning the carrier-envelope offset frequency, is discussed. High average power is achieved through chirped-pulse amplification in simple fiber amplifiers based on double-clad photonic crystal fibers. We describe the use of these combs in several applications, including ultrasensitive femtosecond time-resolved spectroscopy and cavity-enhanced high-order harmonic generation.