This study proposes a method for adjusting subwavelength ripple periods and the corresponding double-grating structures formed on fused silica by designing femtosecond laser pulse trains based on localized transient electron density control. Four near-constant period ranges of 190–490 nm of ripples perpendicular to the polarization are obtained by designing pulse trains to excite and modulate the surface plasmon waves. In the period range of 350–490 nm, the double-grating structure is fabricated in one step, which is probably attributable to the grating-assisted enhanced energy deposition and subsequent thermal effects.
© 2013 Optical Society of America
Lasers and Laser Optics
Original Manuscript: June 4, 2013
Revised Manuscript: August 21, 2013
Manuscript Accepted: August 26, 2013
Published: September 17, 2013
Xuesong Shi, Lan Jiang, Xin Li, Sumei Wang, Yanping Yuan, and Yongfeng Lu, "Femtosecond laser-induced periodic structure adjustments based on electron dynamics control: from subwavelength ripples to double-grating structures," Opt. Lett. 38, 3743-3746 (2013)