Nonlinear Diffraction from a Virtual Beam

Nonlinear diffraction from a virtual beam.

We observe experimentally a novel type of nonlinear diffraction in the process of two-wave mixing on a nonlinear quadratic grating. We demonstrate that when the nonlinear grating is illuminated simultaneously by two noncollinear beams, a second-harmonic diffraction pattern is generated by a virtual beam propagating along the bisector of the two pump beams. The observed diffraction phenomena is ...

Diffraction-limited polarized emission from a multimode ytterbium fiber amplifier after a nonlinear beam converter.

The multimode and depolarized output beam of a highly multimode diode-pumped Yb-doped fiber amplifier is converted to a diffraction-limited, linearly polarized beam by a self-referencing two-wave-mixing process in an infrared-sensitive photorefractive crystal (Rh:BaTiO3). As much as 11.6 W of single-mode output is achieved with a 78% multimode-to-single-mode photorefractive conversion efficiency.

Nonlinear cusp diffraction catastrophe and vortex quadrupoles from a smooth initial beam

Self-action effects such as self-defocusing and self-bending are well-known nonlinear optical phenomenon dating back to the 1960s. Until recently the so-called blooming or lensing effect of a symmetric beam has been a main topic of investigation. A smaller number of experiments using asymmetric beams were reported (see, for example Khoo, Golub, and Swartzlander.) Whereas many early experiments ...

Nonlinear Vibration Analysis of a cantilever beam with nonlinear geometry

Analyzing the nonlinear vibration of beams is one of the important issues in structural engineering. According to this, an impressive analytical method which is called Modified Iteration Perturbation Method (MIPM) is used to obtain the behavior and frequency of a cantilever beam with geometric nonlinear. This new method is combined by the Mickens and Iteration methods. Moreover, this method don...

Optical Diffraction Radiation from a beam off a circular target