Related papers: Efficient multiphoton microscopy with picosecond l…
We demonstrate a compact watt-level all polarization-maintaining (PM) femtosecond fiber laser source at 1100 nm. The fiber laser source is seeded by an all PM fiber mode-locked laser employing a nonlinear amplifying loop mirror. The seed…
Raman amplification in plasma has been promoted as a means of compressing picosecond optical laser pulses to femtosecond duration to explore the intensity frontier. Here we show for the first time that it can be used, with equal success, to…
Research on multimode optical fibers is arousing a growing interest, for their capability to transport high-power laser beams, coupled with novel nonlinear optics-based applications. However, when beam intensities exceed a certain critical…
We demonstrate compression and shaping of few cycle pulses from a high average power Ytterbium laser system. The pulses from a commercial 20 W, 100 kHz Yb laser system are spectrally broadened in two-stages using gas-filled, stretched…
Filamentation has extensively been explored and is well understood at repetition rates <1 kHz due to the typical availability of multi-mJ laser systems at a moderate average power. The advent of high-power Yb-lasers opened new possibilities…
We report the application of fifth order nonlinear optical processes for multiphoton microscopy, including fifth harmonic and 5-photon excitation fluorescence. This novel imaging modality has been characterized with spectral and power…
A compact, strictly all-fiber, picosecond pulse source based on ytterbium (Yb) doped fiber is described. Stable solitary mode-locking is obtained in a fiber-oscillator utilizing a carefully designed chirped fiber-Bragg-grating (C-FBG) for…
Few-cycle pulses present an essential tool to track ultrafast dynamics in matter and drive strong field effects. To address photon-hungry applications, high average power lasers are used which, however, cannot directly provide sub-100 fs…
We present an entirely fiber based laser source for non-linear imaging with a novel approach for multi-color excitation. The high power output of an actively modulated and amplified picosecond fiber laser at 1064 nm is shifted to longer…
Applications of terawatt-class lasers can enormously benefit from pulse trains with kHz repetition rates. The associated unprecedented combinations of peak and average powers require the development of new concepts for scalable ultrashort…
Over the past years, ultrafast lasers with average powers in the 100 W range have become a mature technology, with a multitude of applications in science and technology. Nonlinear temporal compression of these lasers to few- or even…
An exciting recent development for deep-tissue imaging with cellular resolution is three-photon fluorescence microscopy (3PM) with excitation at long wavelengths (1300 and 1700 nm). In the last few years, long-wavelength 3PM has driven…
Highly nonlinear optical processes, such as multiphoton photoemission, require high intensities, typically achieved with ultrashort laser pulses and, hence, were first observed with the advent of picosecond laser technology. An alternative…
We report on an environmentally stable, Yb-doped, all-normal dispersion, mode-locked fibre laser that is capable of creating broadband pulses with ultra-low repetition rates. Specifically, through careful positioning of fibre sections in an…
Two-photon excited fluorescence (TPEF) microscopy and fluorescence lifetime imaging (FLIM) are powerful imaging techniques in bio-molecular science. The need for elaborate light sources for TPEF and speed limitations for FLIM, however,…
Synchronising ultra-short (~fs) and focussed laser pulses is a particularly difficult task, as this timescale lies orders of magnitude below the typical range of fast electronic devices. Here we present an optical technique that allows for…
High peak power ultrafast lasers are widely used in nonlinear spectroscopy but often limit its spectral resolution because of the broad frequency bandwidth of ultrashort laser pulses. Improving the resolution by achieving spectrally narrow…
The quantum cascade laser (QCL) has evolved to be a compact, powerful source of coherent mid-infrared (mid-IR) light. However, its fast gain dynamics strongly restricts the formation of ultrashort pulses. As such, the shortest pulses…
We experimentally demonstrate a novel nonlinear effect in optical fibers: upconversion luminescence generation excited by multiphoton absorption of femtosecond infrared pulses. We directly estimate the average number of photons involved in…
Nonlinear amplification is a powerful technique for generating ultrashort laser pulses with high peak power in fiber systems. However, the diversity of nonlinear amplification approaches and their inherent complexities present significant…