Addressing modulational instability in anti-resonant hollow-core fibers for pulse compression

TL;DR

This paper investigates how to control modulational instability in anti-resonant hollow-core fibers to improve pulse compression stability through experimental and numerical analysis.

Contribution

It demonstrates that selecting specific wall thicknesses in AR-HCFs can significantly suppress MI, enabling higher energy stable pulse compression.

Findings

Reducing MI gain increases stable pulse energy limits.

Wall thickness of AREs influences MI suppression.

Experimental and simulation results agree on MI control methods.

Abstract

When pulses propagate in gas-filled anti-resonant hollow-core fibers (AR-HCFs) modulational instability (MI) can lead to pulse break-up and loss of coherence. In pulse broadening and compression schemes, MI is a parasitic effect that induces significant shot-to-shot fluctuations of the peak power of compressed pulses and increases rapidly over a narrow range of input pulse energies. In this work we use experimental studies and supporting numerical simulations to compare two AR-HCFs that are chosen to enhance or suppress MI. We demonstrate that judicious selection of the wall thickness of the anti-resonant elements (AREs) can drastically reduce the MI gain, thereby increasing the limit of pulse energy scaling of stable ultrafast pulse compression.