Second Harmonic Generation From Short Pulses

Abstract

The second harmonic pulse shape generated from ultrashort pulses is calculated. In long dispersive crystals the pulse width may be much broader than the incident pulse and the power conversion ratio may saturate at a low value. These effects should be prominent in LiNbO3 with 4 × 10−13 sec pulses.

Theory of backward second-harmonic generation of short laser pulses in periodically and aperiodically poled nonlinear crystals

“…We can derive the BSHG efficiency in the plane wave approximation if the following conditions are satisfied: L NES L, L DIS,i L, and L NEL L [30,31]. Under these conditions, one obtains the following solution for the BSHG efficiency (see also [17]):…”

Optical harmonic generation and laser light frequency mixing processes in nonlinear media

“…The time of duration of ultrashort pulses (10-11 to 10-13 sec) is comparable to the relaxation time of molecules, the time required for nonlinearities to become steady [152], and the times of group-wise delay of light waves co-operating in a medium. This group delay time, which defines the wave unstationarities, is in principle essential to the processes of harmonic generation and parametric processes caused by ultrashort pulses [145,148,153].…”

“…From a theoretical analysis [ 145,146] of SHG by ultrashort pulses, Shapiro [147] proceeded to an investigation of the duration of the second harmonic of short Nd-glass laser pulses as a function of the length of a LiNbO3 crystal. Orlov et al [148] studied extensively the spectral and angular distributions of SHG in KDP and LiNbO3 by picosecond Nd-glass laser pulses.…”

Generation and applications of passively mode-locked picosecond light pulses

“…Second harmonic generation of short light pulses is -from the experimental point of view -the simplest method to produce pulses at higher frequencies [63][64][65]. In fact, this technique has been used most frequently.…”