Unidirectional dissipative soliton operation in an-normal-dispersion bidirectional Yb-doped fiber laser without an isolator

TL;DR

This paper demonstrates unidirectional dissipative soliton and noise-like pulse operation in a bidirectional Yb-doped fiber laser without an isolator, achieved through cavity asymmetry and nonlinear polarization rotation mode locking.

Contribution

It introduces a method for unidirectional operation in a bidirectional fiber laser without an isolator using cavity asymmetry and nonlinear polarization rotation.

Findings

Successful self-started unidirectional dissipative soliton operation

Operation of noise-like pulses in the laser

Unidirectionality achieved without an isolator

Abstract

We demonstrate self-started unidirectional dissipative soliton operation and noise-like pulse operation in an all-normal-dispersion bidirectional Yb-doped fiber laser mode-locked by nonlinear polarization rotation. The laser works unidirectional once mode locking was achieved due to the cavity directional nonlinearity asymmetry along with the nonlinear polarization rotation mode locking mechanism.