Hard X-ray generation for Au nanoparticle dispersion was systematically investigated for different particle diameters ranging from 10 to 100 nm with a narrow size distribution of +/- 2%. Scaling law of X-ray generation is close to a 6-photon process before the onset of saturation for excitation by 45 fs laser pulses with central wavelength of 800 nm. This is consistent with bulk plasmon excitation at wavelength ~ 138 nm. The longitudinal E-field component due to nanoparticle focusing is responsible for the excitation of the longitudinal bulk plasmon. The proposed analysis also explains X-ray emission from water breakdown via an electron solvation mechanism at ~6.2 eV. The most efficient emission of X-rays was observed for 40 +/- 10 nm diameter nanoparticles which also had the strongest UV extinction. X-ray emission was the most efficient when induced by pre-chirped 370 +/- 20 fs laser pulses and exhibited the highest intensity at a negative chirp.
Carbon nanotubes decorated with gold, platinum and rhodium clusters by injection of colloidal solutions into the post-discharge of a RF atmospheric plasma
Tracking thermal transport in colloidal quantum dot films using in-situ time-resolved X-ray diffraction
Middlebury College（米德尔伯里学院）；Amherst College（阿默斯特学院）；University of California at Berkeley（加州大学伯克利分校）；Northwestern University（西北大学）；Argonne National Laboratory（阿贡国家实验室）；University of Chicago（芝加哥大学）；Stanford University（斯坦福大学）；University of Vermont（佛蒙特大学）
