Optical-coherence-tomography characterization of free standing electro-optical micro and nanostructures

Thin-film-based LiNbO
₃
components have been experiencing an increasing success over the past decade due to their potentiality to enhance electro-optical (EO) or nonlinear (NL) effects [1, 2]. Therefore, their production at low cost is becoming a major challenge. In [3, 4], we proposed a precise-dicing-based technique for the low-cost production of confined LiNbO
₃
waveguides with integrated spot-size-converters, and we achieved a four-time reduction of the driving power while keeping insertion losses lower than 3 dB. Here we go one step further by proposing free-standing electro-optical micro and nanostructures in sub-micrometer-thin layers of LiNbO
₃
. We also employ an optical-coherence-tomography (OCT)-based characterization method to evaluate the birefringence, group velocity, propagation losses, and electro-optical sensitivity of the membranes.