Realization and characterization of a low intensity noise ultrafast Yb-doped fiber amplifier

TL;DR

This paper presents the design and comprehensive characterization of low-noise, cost-effective Yb-doped fiber amplifiers operating at room temperature, capable of amplifying ultrafast pulses with high power and minimal noise increase.

Contribution

It introduces two experimental configurations of Yb-doped fiber amplifiers with detailed performance analysis and noise characterization, demonstrating high power and low noise operation.

Findings

Amplified output power exceeds 2 W in both configurations

No significant noise degradation during amplification

Successful amplification of ultrafast pulses with minimal noise increase

Abstract

We report on the design and whole characterization of low-noise and affordable-cost Yb-doped double-clad fiber amplifiers operating at room temperature in the near-infrared spectral region at pulse repetition rate of 160 MHz. Two different experimental configurations are discussed. In the first one, a broadband seed radiation with a transform limited pulse duration of 71 fs, an optical spectrum of 20 nm wide at around 1040 nm, and 20 mW average power is adopted. In the second configuration, the seed radiation is constituted by stretched pulses with a time duration as long as 170 ps, with a 5-nm narrow pulse spectrum centered at 1029 nm and 2 mW average input power. In both cases we obtained transform limited pulse trains with an amplified output power exceeding 2 W. Furthermore, relative intensity noise measurements show that no significant noise degradation occurs during the amplification process.