High-efficiency generation of pulsed Lyman-α radiation by resonant laser wave mixing in low pressure Kr-Ar mixture.

We report an experimental generation of ns pulsed 121.568 nm Lyman-α radiation by the resonant nonlinear four-wave mixing of 212.556 nm and 845.

Design for sequentially timed all-optical mapping photography with optimum temporal performance.

A recently developed ultrafast burst imaging method known as sequentially timed all-optical mapping photography (STAMP) [Nat. Photonics8, 695 (2014)10.1038/nphoton.

Phase locking in a Nd:YVO₄ waveguide laser array using Talbot cavity.

We demonstrated phase-locking in a laser-diode-array-pumped Nd:YVO₄ laser array (15 emitters) using a Talbot cavity. The Nd:YVO₄ slab crystal was coated by dielectric material for claddings and formed a planar waveguide for the vertical mode. To stabilize the horizontal array mode, periodical thermal lenses were generated by controlling the heat flow.

Temporal control of local plasmon distribution on Au nanocrosses by ultra-broadband femtosecond laser pulses and its application for selective two-photon excitation of multiple fluorophores.

We theoretically demonstrate spatiotemporal control of local plasmon distribution on Au nanocrosses, which have different aspect ratios, by chirped ultra-broadband femtosecond laser pulses. We also demonstrate selective excitation of fluorescence proteins using this spatiotemporal local plasmon control technique for applications to two-photon excited fluorescence microscopy.

Generation of extreme ultraviolet continuum radiation driven by a sub-10-fs two-color field.

We have proposed and demonstrated a novel approach for generating high-energy extreme-ultraviolet (XUV) continuum radiation. When a two-color laser field consisting of a sub-10-fs fundamental and its parallel-polarized second harmonic was applied to high-order harmonic generation in argon, a continuum spectrum centered at 30 nm was successfully obtained with an energy as high as 10 nJ. This broadband emission indicates the possibility of generating intense single attosecond pulses in the XUV region.

Attenuation of photobleaching in two-photon excitation fluorescence from green fluorescent protein with shaped excitation pulses.

The two-photon excitation fluorescence (TPEF) process of an enhanced green fluorescent protein (EGFP) for fluorescence signals was adaptively controlled by the phase-modulation of femtosecond pulses. After the iteration of pulse shaping, a twofold increase in the ratio of the fluorescence signal to the laser peak power was achieved. Compared with conventional pulses optimized for peak power, phase-optimized laser pulses reduced the bleaching rate of EGFP by a factor of 4 while maintaining the same intensity of the fluorescence signal.