Two-photon excitation of surface plasmon and the period-increasing effect of low spatial frequency ripples on a GaP crystal in air/water. (3rd October 2016)

• Record Type: Journal Article
• Authors: Liu, Jukun; Jia, Tianqing; Zhao, Hongwei; Huang, Yaoqing
• Is Part Of: Journal of physics. Volume 49:Number 43(2016)
• Publication Date: 2016-10-03
• Subjects: laser-induced periodic surface structures -- GaP crystal -- two-photon absorption -- surface plasmon -- period-increasing effect; Physics -- Periodicals; 530
• DOI: 10.1088/0022-3727/49/43/435105
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: We report the period-increasing effect of low spatial frequency ripples on a GaP crystal irradiated by 1 kHz, 50 fs, 800 nm femtosecond laser pulses. Massive free electrons are excited by a two-photon absorption process and surface plasmon is excited. The Drude model is used to estimate the changing of the dielectric constant of the GaP crystal. The period-increasing effects of low spatial frequency laser-induced ripples are theoretically predicted in air/water, and the experimental results agree well. The experimental and theoretical results indicate that surface plasmon excited by two-photon absorption plays a key role in the formation of low spatial frequency ripples.