1/24/2017 – Logan and LP01 star in a new film about multimode fiber. Based on the paper ‘Self-organized instability in graded-index multimode fibres’.
Gallery Archives
Frank’s talk at Harvard
11/03/2016 – Prof Wise gave the Lester Wolfe lecture at the Wellman Center for Photomedicine, Harvard Medical School.
Xiang’s seminar
Logan’s talk 2016
Wise group at 4H 2016
Frank’s webinar
06/22/2016 – Frank gives OSA Webinar on “Spatiotemporal Dynamics of Optical Pulse Propagation in Multimode Fibers.” Check it out!
Self-similar pulse evolution in a fiber laser with a comb-like dispersion-decreasing fiber
Self-similar pulse evolution in a fiber laser with a comb-like dispersion-decreasing fiber
We demonstrate an erbium fiber laser with self-similar pulse evolution inside a comb-like dispersion-decreasing fiber (DDF), which has the potential of generating nJ-level few-cycle pulses directly from a fiber oscillator. A passive DDF is formally equivalent to a fiber with constant gain, and can thus support self-similar pulse evolution but without any bandwidth limitation. Considering the challenges to fabrication of DDF, we try to imitate an ideal DDF with a comb-like DDF based on segments of ordinary fibers, which offers major practical advantages. The laser generates 1.3 nJ pulses with parabolic shapes and linear chirps, which can be dechirped to 37 fs. This constitutes a 4-fold increase in pulse energy compared to previous reports of this pulse duration.
Generation of 8 nJ pulses from a normal-dispersion thulium fiber laser
Generation of 8 nJ pulses from a normal-dispersion thulium fiber laser
There is great interest in development of better short-pulse lasers in the 2-5 μm region. We show the first thulium-doped fiber laser at 2 μm to reap the performance benefits of pulse propagation at normal dispersion. Ultra-high numerical-aperture fibers provide normal dispersion and are employed to shift the cavity dispersion to the normal regime. A laser that exhibits elements of self-similar pulse evolution generates 8-nJ and 130-fs pulses, which corresponds to 4 times the highest peak power achieved previously by a Tm fiber laser.
Spatiotemporal dynamics of multimode optical solitons
Spatiotemporal dynamics of multimode optical solitons
We launch pulses into multimode fiber, exciting multiple spatial modes. We show how nonlinear interactions between the modes give rise to a multimode soliton. A multimode soliton is a non-dispersing wavepacket that contains several distinct spatial mode components, and propagates through the fiber without changing its shape due to a balance between nonlinear and linear effects. We observe spatiotemporal soliton fission – the disintegration of an optical pulse into distinct multimode soliton components with different spatiotemporal properties. Lastly, we observe the effect of stimulated Raman scattering on multimode solitons. This causes them to shift to longer wavelengths, while maintaining their multimode soliton characteristics.
Ultrafast fiber lasers based on self-similar pulse evolution: a review of current progress
Ultrafast fiber lasers based on self-similar pulse evolution: a review of current progress
We summarize the state of research on lasers based on self-similar pulse evolutions, including passive similariton, amplifier similariton, and others. Self-similar fiber lasers are conceptually different from other kinds of short-pulse lasers. This distinction allows for exciting new laser design options.