Open AccessProduction rate enhancement of size-tunable silicon nanoparticles by temporally shaping femtosecond laser pulses in ethanol
Author(s) -
Xin Li,
Guangming Zhang,
Lan Jiang,
Xuesong Shi,
Kaihu Zhang,
Wenlong Rong,
Ji’an Duan,
Yongfeng Lu
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.004226
Subject(s) - materials science , femtosecond , silicon , optics , pulse (music) , nanoparticle , laser , femtosecond pulse , optoelectronics , nanotechnology , physics , detector
This paper proposes an efficient approach for production-rate enhancement and size reduction of silicon nanoparticles produced by femtosecond (fs) double-pulse ablation of silicon in ethanol. Compared with a single pulse, the production rate is ~2.6 times higher and the mean size of the NPs is reduced by ~1/5 with a delay of 2 ps. The abnormal enhancement in the production rate is obtained at pulse delays Δt > 200 fs. The production-rate enhancement is mainly attributed to high photon absorption efficiency. It is caused by an increase in localized transient electron density, which results from the first sub-pulse ionization of ethanol molecules before the second sub-pulse arrives. The phase-change mechanism at a critical point might reduce nanoparticle size.