We propose a novel configuration of efficient type I second-harmonic generation (SHG) with ultrashort laser pulses by group-velocity compensation. The configuration is composed of a type I SHG crystal and a series of alternating time-delay and type I SHG crystals. The numerical calculations show that the conversion efficiency can be increased to almost 100% by using crystal pairs in series, and the duration of the second-harmonic pulse is almost the same as that of the fundamental pulse.
© 1998 Optical Society of America
(190.0190) Nonlinear optics : Nonlinear optics
(190.4160) Nonlinear optics : Multiharmonic generation
(190.4400) Nonlinear optics : Nonlinear optics, materials
(320.5550) Ultrafast optics : Pulses
Tiejun Zhang and Motoki Yonemura, "Efficient Type I Second-Harmonic Generation of Subpicosecond Laser Pulses with a Series of Alternating Nonlinear and Delay Crystals," Appl. Opt. 37, 1647-1650 (1998)