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From Ewald sphere to Ewald shell in nonlinear optics.

ABSTRACT: Ewald sphere is a simple vector scheme to depict the X-ray Bragg diffraction in a crystal. A similar method, known as the nonlinear Ewald sphere, was employed to illustrate optical frequency conversion processes. We extend the nonlinear Ewald sphere to the Ewald shell construction. With the Ewald shell, a variety of quasi-phase-matching (QPM) effects, such as the collective envelope effect associated with multiple QPM resonances, the enhanced second- harmonic generation due to multiple reciprocal vectors etc., are suggested theoretically and verified experimentally. By rotating the nonlinear photonic crystal sample, the dynamic evolution of these QPM effects has also been observed, which agreed well with the Ewald shell model.

SUBMITTER: Huang H

PROVIDER: S-EPMC4937392 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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From Ewald sphere to Ewald shell in nonlinear optics.

Huang Huang H Huang Cheng-Ping CP Zhang Chao C Hong Xu-Hao XH Zhang Xue-Jin XJ Qin Yi-Qiang YQ Zhu Yong-Yuan YY

Scientific reports 20160708

Ewald sphere is a simple vector scheme to depict the X-ray Bragg diffraction in a crystal. A similar method, known as the nonlinear Ewald sphere, was employed to illustrate optical frequency conversion processes. We extend the nonlinear Ewald sphere to the Ewald shell construction. With the Ewald shell, a variety of quasi-phase-matching (QPM) effects, such as the collective envelope effect associated with multiple QPM resonances, the enhanced second- harmonic generation due to multiple reciproca ...[more]

PMID: 27386951

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