# CEP-stable high-energy ytterbium doped fiber amplifier

## TL;DR

This paper demonstrates a CEP-stable high-energy ytterbium-doped fiber amplifier system capable of delivering 100 fs pulses at 100 kHz with sub-radian CEP stability, suitable for attoscience applications.

## Contribution

It introduces a hybrid CEP stabilization architecture combining passive and active methods for high-energy Yb-doped fiber amplifiers, achieving record stability levels.

## Key findings

- CEP standard deviation of 320 mrad rms over 1 second
- Long-term CEP stability of 380 mrad over one hour
- Compatible with high-repetition-rate attosecond science applications

## Abstract

We report on the CEP stabilization of an Yb-doped fiber amplifier system delivering 30 microjoules, 100 fs pulses at 100 kHz repetition rate. A single shot, every shot, measurement of the CEP stability based on a simple f-2f interferometer is performed, yielding a CEP standard deviation of 320 mrad rms over 1 s. Long-term stability is also assessed, with 380 mrad measured over one hour. This level of performance is allowed by a hybrid architecture including a passively CEP-stabilized front-end based on difference frequency generation, and an active CEP stabilization loop for the fiber amplifier system, acting on a telecom-grade integrated LiNbO3 phase modulator. These results demonstrate the full compatibility of Yb-doped high repetition rate laser for attoscience.

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Source: https://tomesphere.com/paper/1903.12418