Abstract

The confocal microscopy technique was applied for nonlinear optical characterization of single β-barium-borate (β-BBO) nanocrystals. The experimental setup allows measurements of the laser polarization-selective second-harmonic (SH) generation, and the results can be used to determine the nanocrystals’ c-axis orientation, as well as to obtain information about their second-order susceptibility χ⁽²⁾. The dependence of the SH signal on the laser polarization allowed the discrimination of individual particles from aggregates. The data were fitted using a model that takes into account the BBO properties and the experimental setup characteristics considering (i) the electrostatic approximation, (ii) the effects of the microscope objective used to focus the light on the sample in an epi-geometry configuration, and (iii) the symmetry of χ⁽²⁾ for the β-BBO nanocrystals. A signal at the third-harmonic frequency was also detected, but it was too weak to be studied in detail.

© 2018 Chinese Laser Press

Second to fifth harmonic generation in individual β-barium borate nanocrystals

Thomas Possmayer, Benjamin Tilmann, Lauro J. Q. Maia, Stefan A. Maier, and Leonardo de S. Menezes
Opt. Lett. 47(7) 1826-1829 (2022)

Conical emission in β-barium borate under femtosecond pumping with phase matching angles away from second harmonic generation

S. Akbar Ali, P. B. Bisht, A. Nautiyal, V. Shukla, K. S. Bindra, and S. M. Oak
J. Opt. Soc. Am. B 27(9) 1751-1756 (2010)

Efficient second harmonic generation in β-barium borate by a diffraction-limited copper vapor laser

R. Pini, R. Salimbeni, G. Toci, and M. Vannini
Appl. Opt. 31(15) 2747-2751 (1992)

Cascaded second-order effects in the femtosecond regime in β-barium borate: self-compression in a visible femtosecond optical parametric oscillator

F. Hache, A. Zéboulon, G. Gallot, and G. M. Gale
Opt. Lett. 20(14) 1556-1558 (1995)

Electro-optically tunable cascaded second-order nonlinearity induced (2 + 1)D spatial optical soliton using bulk β-barium borate crystal: a theoretical approach

Sharbari Deb, Satadru Behera, and Ardhendu Saha
J. Opt. Soc. Am. B 39(12) 3311-3319 (2022)