Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userXPM-forced frequency-oscillating soliton in mode-locked fiber laser
122
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
Cross phase modulation (XPM) could induce soliton trapping in nonlinear medium, which has been employed to achieve vector soliton, optical switching and optical analog of gravity-like potentials. These results are generally within the definition in Hamilton system. Here, we report on the observation of a XPM-forced frequency-oscillating soliton (XFOS) whose wavelength exhibits redshift and blueshift periodically like dancing in a mode-locked fiber laser under moderate birefringence. XFOS consists of two orthogonally polarized components exhibiting simultaneous frequency oscillation driven by XPM and gain effect, which allows withstanding higher pulse energy. The pulse trapping is maintained by differentiating the frequency-shift rate. Numerical simulations agree very well with experimental results, revealing an idiosyncratic evolution dynamic for asymmetry pulses in nonlinear dissipative system and envisaging a technique to control pulse feature with preset pulse chirp. XFOS may exist generally in polarization-independent ultrafast lasers, which enriches soliton family and brings useful insights into nonlinear science and applications.
rate research
Read More
By means of the emerging Dispersive Fourier transformation technique, we captured the pulse-resolved spectral evolution dynamics of the double-soliton (DS) states in a single-walled carbon nanotube based Er-doped fiber laser from the initial fluctuations, monitoring the evolution process up to 10 seconds (corresponding to ~260 million roundtrips) discontinuously. Two distinctly different evolutionary types of DS states have been investigated in detail: splitting from one pulse and forming simultaneously. Relaxation oscillations, beating, transient bound state, spectral broadening and pulse interval dynamics have been observed in the evolution process of the DS operation. Our study will be helpful for the further research of mode-locking operation.
Atomic layer graphene possesses wavelength-insensitive ultrafast saturable absorption, which can be exploited as a full-band mode locker. Taking advantage of the wide band saturable absorption of the graphene, we demonstrate experimentally that wide range (1570 nm - 1600nm) continuous wavelength tunable dissipative solitons could be formed in an erbium doped fiber laser mode locked with few layer graphene.
114 -
Alexey Andrianov
, Arkady Kim (Institute of Applied Physics of then Russian Academy of Sciences
, Nizhny Novgorod
2019
We present the first direct observation of the bound state of multiple dissipative optical solitons in which bond length and bond strength can be individually controlled in a broad range in a regular manner. We have observed experimentally a new type of stable and extremely elastic soliton crystals that can be stretched and compressed many times conserving their structure by adjusting the bond properties in real time in a specially designed passively mode-locked fiber laser incorporating highly asymmetric tunable Mach-Zehnder interferometer. The temporal structure and dynamics of the generated soliton crystals have been studied using an asynchronous optical sampling system with picosecond resolution. We demonstrated that stable and robust soliton crystal can be formed by two types of primitive structures: single dissipative solitons, and(or) pairs of dissipative soliton and pulse with lower amplitude. Continuous stretching and compression of a soliton crystal with extraordinary high ratio of more than 30 has been demonstrated with a smallest recorded separation between pulses as low as 5 ps corresponding to an effective repetition frequency of 200 GHz. Collective pulse dynamics, including soliton crystal self-assembling, cracking and transformation of crystals comprising pulse pairs to the crystals of similar pulses has been observed experimentally.
We study experimentally and theoretically the interactions among ultrashort optical pulses in the soliton rain multiple-pulse dynamics of a fiber laser. The laser is mode-locked by a graphene saturable absorber fabricated using the mechanical transfer technique. Dissipative optical solitons aggregate into pulse bunches that exhibit complex behavior, which includes acceleration and bi-directional motion in the moving reference frame. The drift speed and direction depend on the bunch size and relative location in the cavity, punctuated by abrupt changes under bunch collisions. We model the main effects using the recently proposed noise-mediated pulse interaction mechanism, and obtain a good agreement with experiments. This highlights the major role of long-range Casimir-like interactions over dynamical pattern formations within ultrafast lasers.
High frequency fluctuation in the optical signal generated in Fourier-Domain Mode Locked fiber laser (FDML-FL), which is the major problem and degrades the laser performance, is not yet fully analyzed or studied. The basic theory which is causing this high frequency fluctuation is required to clearly understand its dynamics and to control it for various applications. In this letter, by analyzing the signal and system dynamics of FDML-FL, we theoretically demonstrate that the high frequency fluctuation is induced by the intrinsic instability of frequency offset of the signal in cavity with nonlinear gain and spectral filter. Unlike the instabilities observed in other laser cavities this instability is very unique to FDML-FL as the central frequency of the optical signal continuously shifts away from the center frequency of the filter due to the effects like dispersion and/or nonlinearity. This instability is none other than the Eckhaus instability reported and well studied in fluid dynamics governed by real Ginzburg-Landau equation.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
