Ultrabroadband, few-cycle pulses directly from a Mamyshev fiber oscillator

While the performance of mode-locked fiber lasers has been improved significantly, the limited gain bandwidth restricts them from generating ultrashort pulses approaching a few cycles or even shorter. Here we present a novel method to achieve few-cycle pulses ($∼5 cycles$) with an ultrabroad spectrum ($∼400 nm$at$−20 dB$) from a Mamyshev oscillator configuration by inserting a highly nonlinear photonic crystal fiber and a dispersion delay line into the cavity. A dramatic intracavity spectral broadening can be stabilized by the unique nonlinear processes of a self-similar evolution as a nonlinear attractor in the gain fiber and a “perfect” saturable absorber action of the Mamyshev oscillator. To the best of our knowledge, this is the shortest pulse width and broadest spectrum directly generated from a fiber laser.

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Award ID(s):
Publication Date:
NSF-PAR ID:
10127996
Journal Name:
Photonics Research
Volume:
8
Issue:
1
Page Range or eLocation-ID:
Article No. 65
ISSN:
2327-9125
Publisher:
Optical Society of America
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