Saturable absorption optimization of silica protected thin Sb2Te3 layers towards super-resolution applications.

Abstract Sb 2 Te 3 thin films are very promising candidates for nonlinear optics and several applications including super-resolution and nano-photoinscription. This work aims to offer a detailed study of the preparation of the thin films and their nonlinear optical properties under nanosecond laser excitation. Thin Sb 2 Te 3 films have been deposited by the electron beam deposition technique. The films have been protected by a thin silica layer, then annealed in order to enhance their nonlinearities by material crystallization. The annealing has been optimized by simultaneously recording the X-Ray diffraction diagrams. After this optimization, the annealing could be safely performed by heating in an oven. The nonlinear optical properties of the Sb 2 Te 3 thin films have been studied by means of the Z-scan technique employing 11 ns laser pulses at 1064 nm and 532 nm. High nonlinear absorption has been found showing the possibility to employ these materials for super-resolution, mode-locking and other applications. Highlights • Structure optimization of Sb 2 Te 3 thin films to enhance the optical nonlinearities. • Significant nonlinear absorption has been detected by means of the Z-scan technique. • The samples can be used for super-resolution at the visible and the NIR. [ABSTRACT FROM AUTHOR]