Anomalous Second Harmonic Generation of Twisted Gaussian Schell Model Beams

M. Gil de Oliveira; A. L. S. Santos Junior; A. C. Barbosa; B. Pinheiro da Silva; G. H. dos Santos; G. Cañas; P. H. Souto Ribeiro; S. P. Walborn; A. Z. Khoury

arXiv · 2403.04040

Anomalous Second Harmonic Generation of Twisted Gaussian Schell Model Beams

M. Gil de Oliveira·A. L. S. Santos Junior·A. C. Barbosa·B. Pinheiro da Silva·G. H. dos Santos·G. Cañas·P. H. Souto Ribeiro·S. P. Walborn·A. Z. Khoury

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Abstract

We investigate theoretically and experimentally the optical second harmonic generation (SHG) with a twisted Gaussian Schell model (TGSM) beam as the fundamental field. We use Type-II phase matching and analyze the cross spectral density (CSD) of the SHG output beam when the input fundamental is prepared with a TGSM structure. We analyze two synthetization methods for preparing the TGSM fundamental beam and we find that for one method the SHG is also a TGSM beam. For the other method, we find that the SHG is not a TGSM beam and presents an anomalous CSD possessing a dip instead of a peak in the transverse spatial structure. Moreover, we show that the dip depth is directly related to the twisted phase parameter, being absent for a non twisted GSM beam. Our results show that the SHG from a fundamental TGSM beam can result in a doubled frequency TGSM or in a non-TGSM beam depending on the synthetization method.

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M. Gil de Oliveira, A. L. S. Santos Junior, A. C. Barbosa, B. Pinheiro da Silva, G. H. dos Santos, G. Cañas, P. H. Souto Ribeiro, S. P. Walborn, A. Z. Khoury. 2024-03-06. Anomalous Second Harmonic Generation of Twisted Gaussian Schell Model Beams. https://arxiv.org/abs/2403.04040

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