Analytical theory of second harmonic generation from a nanowire with noncentrosymmetric geometry


Por: Singla, Raksha, Luis Mochan, W.

Publicada: 14 mar 2019
Resumen:
We analytically investigate the effect of a noncentrosymmetric geometry in the optical second harmonic (SH) generation from a nanowire made of a centrosymmetric material, in the interior of which quadratic optical processes are suppressed. We consider an infinite cylinder with a cross section that is slightly deformed away from a circle and with a radius much smaller than the wavelength. We calculate the induced linear and nonlinear fields perturbatively in terms of the deformation parameter, and we obtain the nonlinear dipolar and quadrupolar hyperpolarizabilities, whose spectra we evaluate for metallic and dielectric materials. We show that for very small deformations, the dipolar contribution to the response competes with the quadrupolar term, and may even be dominant. We explore the spectra of the hyperpolarizability and identify the contributions to its structure for metallic and dielectric nanowires. We also discuss the nature of the SH radiation at various frequencies, and we find that it may be dominated by the dipolar or the quadrupolar term, or that both may compete yielding nonsymmetric radiation patterns. Our calculation may be employed to assess, calibrate, and test numerical SH calculations.

Filiaciones:
Singla, Raksha:
 Univ Nacl Autonoma Mexico, Inst Ciencias Fis, Apartado Postal 48-3, Cuernavaca 62251, Morelos, Mexico

 Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Apartado Postal 48-3, Cuernavaca, Morelos, 62251, Mexico

Luis Mochan, W.:
 Univ Nacl Autonoma Mexico, Inst Ciencias Fis, Apartado Postal 48-3, Cuernavaca 62251, Morelos, Mexico
ISSN: 24699950
Editorial
AMER PHYSICAL SOC, ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA, Estados Unidos America
Tipo de documento: Article
Volumen: 99 Número: 12
Páginas:
WOS Id: 000461962400003

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