Supplementary document for Nonlinear ultrafast fiber amplifiers beyond the gain-narrowing limit - 4148703.pdf

supplementary materia

Nonlinear ultrafast fiber amplifiers beyond the gain-narrowing limit

Ultrafast lasers are becoming increasingly widespread in science and industry alike. Fiber-based ultrafast laser sources are especially attractive because of their compactness, alignment-free setups, and potentially low costs. However, confining short pulses within a fiber core leads to high intensities, which drive a host of nonlinear effects. While these phenomena and their interactions greatly complicate the design of such systems, they can also provide opportunities for engineering new capabilities. Here, we report a new fiber amplification regime distinguished by the use of a dynamically-evolving gain spectrum as a degree of freedom: as a pulse experiences nonlinear spectral broadening, absorption and amplification actively reshape both the pulse and the gain spectrum itself. The dynamic co-evolution of the field and excited-state populations supports pulses that can broaden spectrally by almost two orders of magnitude and well beyond the gain bandwidth, while remaining cleanly-compressible to their sub-50-fs transform limit. Theory and experiments provide evidence that a nonlinear attractor underlies the management of the nonlinearity by the gain. Further research into the mutual, pulse-inversion propagation dynamics may address open scientific questions and pave the way toward simple, compact fiber sources that produce high-energy, sub-30-fs pulses

Starting Dynamics of a Fully Electronically Controlled Linear Mamyshev Oscillator

We start an environmentally-stable linear Mamyshev oscillator with electronically-controlled modulated pump and a moving filter. It delivers a 21-nJ pulse that becomes 65 fs in duration after a compressor. Reliable starting into stable mode-locking is found achievable with a modulated mode-locked state observed only when the modulation frequency is larger than 70 kHz. To avoid the damage of the gain fiber, two Faraday rotators are introduced. Besides, we have studied several aspects toward obtaining successful starting

Supplementary document for Femtosecond optical parametric chirped-pulse amplification in birefringent step-index fiber - 5533274.pdf

supplemental documen

Multi-megawatt, self-seeded Mamyshev oscillator

We demonstrate a fiber oscillator that achieves 3 MW peak power, is easily started and is environmentally stable. The Mamyshev oscillator delivers 190-nJ pulses that can be compressed externally to 35 fs duration. Accurate numerical modeling of the gain medium provides insight into the behavior and performance of the device

Supplement 1: Ptychographic reconstruction algorithm for frequency-resolved optical gating: super-resolution and supreme robustness

supplementary material Originally published in Optica on 20 December 2016 (optica-3-12-1320

Supplementary document for Efficient soliton self-frequency shift in hydrogen-filled hollow-core fiber - 5547062.pdf

SSFS Supplement

Efficient soliton self-frequency shift in hydrogen-filled hollow-core fiber

We report a study of soliton self-frequency shifting in hydrogen-filled hollow-core fiber. The combination of hydrogen and short 40-fs input pulses underlies clean and efficient generation of Raman solitons between 1080 and 1600 nm. With 240-nJ input pulses, the Raman soliton energy ranges from 110 to 20 nJ over that wavelength range, and the pulse duration is approximately 45 fs. In particular, 70-nJ and 42-fs pulses are generated at 1300 nm. Numerical simulations agree reasonably well with experiments and predict that microjoule-energy tunable pulses should be possible with higher-energy input pulses

Supplementary document for Single-Shot Ptychographic Imaging of Non-Repetitive Ultrafast Events - 6562986.pdf

Supplement

Multimode Mamyshev Oscillator

We present a spatiotemporally mode-locked Mamyshev oscillator. A wide variety of multimode mode-locked states, with varying degrees of spatiotemporal coupling, are observed. We find that some control of the modal content of the output beam is possible through the cavity design. Comparison of simulations to experiments indicates that spatiotemporal mode-locking is enabled by nonlinear intermodal interactions and spatial filtering, along with the Mamyshev mechanism. This work represents a first exploration of spatiotemporal mode-locking in an oscillator with the Mamyshev saturable absorber