Mode-locked fiber laser based on an attenuation-imbalanced nonlinear optical loop mirror

Seong, Nak Hyun; Kim, Dug Y.; Veetil, Suhas P.

doi:10.1016/j.optcom.2007.08.044

“…In all variants of NOLLM, the element inserting losses was placed asymmetrically, close to one of the coupler ports. The total length of the NOLLM was significantly reduced compared to 2x2 equivalents [39,41] and could be shorter than 6 meters.…”

Section: Methodsmentioning

confidence: 87%

“…In the case of a 2x2 NOLLM based on a 50/50 coupler with an attenuator in the loop, the transmissivity additionally depends on the transmission of the attenuator and the position of the attenuator in the loop [22]. Assuming that the attenuator is placed very close to one of the ports of the coupler, the transmissivity can be described as [37,39]:…”

Section: Nonlinear Optical Lossy Loop Mirrormentioning

confidence: 99%

Self-starting mode-locking in an all-PM Yb-doped fiber laser oscillator enabled by a 3x3 nonlinear optical lossy loop mirror

Pielach,

Jamrozik,

Krupa

et al. 2023

Preprint

0

View full text Add to dashboard Cite

Artificial saturable absorbers based on loop mirrors often suffer from a not self-starting mode-locking operation. It is usually necessary to provide an additional phase shift in the loop, guaranteeing repeatable initiation of the pulsed regime. 3x3 even fiber couplers have recently enabled the introduction of a phase shift in an all-fiber loop mirror architecture. Until now, mode-locking induced by a 3x3 fiber coupler has been associated only with nonlinear amplifying loop mirrors. Here, we present a self-starting ultrafast dispersion-managed all-polarization-maintaining Yb-doped oscillator that utilizes a nonlinear optical lossy loop mirror instead. We show three ways of introducing asymmetric losses in a loop via a variable optical attenuator, a fiber coupler, and a very simple lossy splice. Complete characterization of all output ports of the oscillator proves significant spectral and temporal breathing of the pulse when circulating through the net normal dispersion cavity, which can deliver nJ-level pulse energy. The system guarantees excellent stability and performance comparable to nonlinear amplifying loop mirrors while being simpler, cheaper, and providing more usable output ports with different characteristics.

show abstract

“…Apart from placing an amplifier in the loop (resulting in NALM), one can also interpose asymmetric losses [37]. This approach has already been demonstrated in even 50/50 2x2 couplers via a nonlinear absorbing loop mirror (NAbLM [38]), bending the fiber to introduce attenuation-imbalanced NOLM (AI-NOLM [39]), implementing a variable optical attenuator (power-imbalanced NOLM [40]), or placing an additional coupler in the loop [41].…”

Section: Introductionmentioning

confidence: 99%

“…However, inserting the losses in the loop lacking any phase shift may result in moving the mode-locking threshold towards even higher pumping powers or might lead to the necessity of using extreme lengths of fiber in the loop (over fifty meters [39,41]) or using highly nonlinear fibers [40].…”

Section: Introductionmentioning

confidence: 99%

Self-starting mode-locking in an all-PM Yb-doped fiber laser oscillator enabled by a 3x3 nonlinear optical lossy loop mirror

Pielach,

Jamrozik,

Krupa

et al. 2023

Preprint

0

View full text Add to dashboard Cite

Artificial saturable absorbers based on loop mirrors often suffer from a not self-starting mode-locking operation. It is usually necessary to provide an additional phase shift in the loop, guaranteeing repeatable initiation of the pulsed regime. 3x3 even fiber couplers have recently enabled the introduction of a phase shift in an all-fiber loop mirror architecture. Until now, mode-locking induced by a 3x3 fiber coupler has been associated only with nonlinear amplifying loop mirrors. Here, we present a self-starting ultrafast dispersion-managed all-polarization-maintaining Yb-doped oscillator that utilizes a nonlinear optical lossy loop mirror instead. We show three ways of introducing asymmetric losses in a loop via a variable optical attenuator, a fiber coupler, and a very simple lossy splice. Complete characterization of all output ports of the oscillator proves significant spectral and temporal breathing of the pulse when circulating through the net normal dispersion cavity, which can deliver nJ-level pulse energy. The system guarantees excellent stability and performance comparable to nonlinear amplifying loop mirrors while being simpler, cheaper, and providing more usable output ports with different characteristics.

show abstract

“…Passive mode-locking in F8 fibre master oscillators is usually achieved either by means of a non-linear optical loop mirror [1,4,[9][10][11] or with the help of a non-linear amplifying loop mirror (NALM) [2][3][4][5][6][7]. A comparison of laser systems relying on these two types of loop mirrors was carried out in [12], where it was demonstrated that both non-linearity of amplifying loop mirrors and the parameters of generated pulses depend on amplification.…”

Section: Introductionmentioning

confidence: 99%

High average power mode-locked figure-eight Yb fibre master oscillator

Fedotov¹,

Ivanenko²,

Kobtsev³

et al. 2014

View full text Add to dashboard Cite

For the first time, we demonstrate the possibility to generate record-high output radiation power exceeding 1 W in an all-fibre figure-eight mode-locked Yb fibre master oscillator based on non-linear amplifying loop mirror. Generated at the repetition rate of 25 MHz clusters of sub-pulses with duration of no more than 200 fs have envelope width of 23 ps or less. Two typical mode-locked laser regimes with substantially different generation spectra are identified and results of their study presented. Numerical modelling of laser generation in the proposed layout agrees well with the measured experimental data.

show abstract

Mode-locked fiber laser based on an attenuation-imbalanced nonlinear optical loop mirror

Cited by 11 publications

References 9 publications

Self-starting mode-locking in an all-PM Yb-doped fiber laser oscillator enabled by a 3x3 nonlinear optical lossy loop mirror

Self-starting mode-locking in an all-PM Yb-doped fiber laser oscillator enabled by a 3x3 nonlinear optical lossy loop mirror

Self-starting mode-locking in an all-PM Yb-doped fiber laser oscillator enabled by a 3x3 nonlinear optical lossy loop mirror

High average power mode-locked figure-eight Yb fibre master oscillator

Contact Info

Product

Resources

About