Abstract

Thanks to its unique properties such as nonlinear optical and piezo-response [1], LiNbO₃ (LN) has been widely used and studied. Its geometrical and/or domain engineering and functionalization can yield enhanced nonlinear efficiencies, which can be used in new applications such as tissue engineering and bio-sensing [2]. Nanostructuring of LN can further enhance its nonlinearity [3,4]. However, deeper understanding of the role played by the different factors contributing to the nonlinear response [5] as well as accurate Second-Harmonic Generation (SHG) polarimetric mappings [6] are required. Here, we report on the fabrication of high aspect ratio cylindrical nanopillars on X- and Z-cut LN substrates, followed by a systematic study of their SHG polarization properties, to gain insights into the mechanism underlying their local nonlinear response enhancements.

© 2015 IEEE