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Er‐activated fiber lasers are critical for many significant applications, including fiber communication, gas sensing, lidar and military. Although the design of suitable fiber materials has improved the performance of Er‐activated fiber lasers, extension of their operation wavebands still remains a significant challenge. Here, a compact all‐fiber laser is proposed and demonstrated, which can support lasing beyond 1630 nm, based on an Er‐activated hybridized glass fiber. The collaborative theoretical analysis and experimental characterization indicate that various distinct structure units can form in the hybridized fiber. This leads to the notable inhomogeneous spectral broadening. By using this hybridized fiber, a tunable fiber laser device is constructed and the wavelength can be rationally tuned in the range from 1609 to 1631 nm by mechanically stretching the fiber Bragg gratings (FBGs) manufactured by the point‐by‐point femtosecond laser inscription. Furthermore, a new fiber sensor system based on this seldom exploration waveband is built and efficient ethylene detection is demonstrated. The results highlight that rational hybridization mediated short‐ and medium‐structure modification strategy, demonstrated here in Er‐activated fiber laser, can be extended to other rare‐earth glass fiber systems for the exploration of fiber devices at new wavebands. [ABSTRACT FROM AUTHOR]

Ultrafast fiber lasers offer a unique opportunity to implement optically a Poincaré mapping in the phase space of a variety of complex dissipative dynamical systems operating far from the equilibrium. Understanding of such complex optical dynamical systems revealing, for instance, ultrafast dynamics of the dissipative solitons (DSs) and more complex regimes is important for advancing specification and performance of the mode‐locked lasers used in a vast number of applications ranging from spectroscopy and medicine to metrology and telecom. Here, using the mode‐locked fiber laser as a test‐bed, the Shilnikov‐type ultrafast dynamics taking the form of randomly switching between noise‐like pulsing and quasi‐continuous‐wave regimes is experimentally demonstrated. The transient coherence recovery is revealed, during which the noise‐like pulse (NLP) is transformed into a coherent DS state and then returned to an incoherent NLP state. The demonstrated alternation of mode synchronization and desynchronization is both of practical importance for developing new types of partially mode‐locked lasers and of the fundamental interest for the nonlinear science in the context of revealing routes to the turbulence in distributed nonlinear systems. [ABSTRACT FROM AUTHOR]