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We report on a 2.0 PW femtosecond laser system at 800 nm based on the scheme of chirped pulse amplification using Ti:sapphire crystals, which is the highest peak power ever achieved from a femtosecond laser system. Combining the index-matching cladding technique and the precise control of the time delay between the input seed pulse and pump pulses, the(More)
An extremely compact all-fiber-optic scanning endomicroscopy system was developed for two-photon fluorescence (TPF) and second harmonic generation (SHG) imaging of biological samples. A conventional double-clad fiber (DCF) was employed in the endomicroscope for single-mode femtosecond pulse delivery, multimode nonlinear optical signals collection and fast(More)
We report on a new optics design for an optical coherence tomography (OCT) balloon imaging catheter. The design involves a miniature compound gradient-index (GRIN) rod lens, which consists of a fiber optic mode-field reducer and relay rod lenses to achieve predictable high lateral resolution at a desired large working distance. The compound lens design(More)
It is well known that intestinal anaphylaxis results in a disturbed intestinal motility. It is hypothesized that the chronic intestinal anaphylaxis-induced changes in the enteric neuronal circuitry cause intestinal motor malfunctions. However, detailed mechanisms largely remain unclear. The aim of this study was to investigate the pathophysiological role of(More)
New parasitic lasing suppression techniques are developed and high gain amplification is demonstrated in a petawatt level Ti:sapphire amplifier based on the chirped pulse amplification (CPA) scheme. Cladding the large aperture Ti:sapphire with refractive-index matched liquid doped with absorber suppresses the transverse lasing. The acousto-optic(More)
The spectral and the temporal behavior of high-intensity negatively chirped femtosecond pulses in normally dispersive media at different input parameters are experimentally studied. The spectrum of the pulse is reshaped due to strong self-actions. The pulse is self-compressed, instead of broadening, accompanied with the spectral FWHM bandwidth shortened.(More)
We demonstrate what we believe to be a novel tunable IR optical parametric amplifier (OPA) with the passively stabilized carrier-envelope phase (CEP), in which a hollow fiber is used to improve the output beam quality and to overcome the spatial chirp issue. Pumped by an 800 nm pump source, the output pulses are tunable from 1.2 to 2.4 microm with the CEP(More)
The optical parametric-chirped pulse amplification (OPCPA) based on large-aperture nonlinear optical crystals is promising for implementation of an ultrahigh peak-power laser system of 10 PW and beyond. We demonstrated the highest energy broadband OPCPA at 800 nm, to the best of our knowledge, by using an 80 mm in diameter LiB(3)O(5)(LBO) amplifier, with an(More)
A three-stage high conversion efficiency optical parametric amplifier (OPA) with passively stabilized carrier-envelope phase (CEP) is presented. After passing through an argon-filled hollow fiber and the dispersion compensator for pulse compression, CEP stabilized 0.7 mJ, 1.5 cycle laser pulses at 1.75 μm center wavelength are obtained. Terahertz (THz)(More)
Inverse Compton scattering between ultra-relativistic electrons and an intense laser field has been proposed as a major route to generate compact high-brightness and high-energy γ-rays. Attributed to the inherent synchronization mechanism, an all-optical Compton scattering γ-ray source, using one laser to both accelerate electrons and scatter via the(More)