Fabrication of three-dimensional plasmonic structure and multilayer metamaterials by femtosecond laser-induced forward transfer

Abstract

Plasmonic metamaterials, composed by arti?cial micro or nanostructures, exhibit extraordinary optical properties such as negative refraction, which cannot be observed in nature. The focused ion beam (FIB) and electron beam lithography (EBL) technique are frequently adopted to fabricate multilayer and three-dimensional plasmonic structures, but the alignment error, high cost and time consuming cannot be avoided. In contrast, the laser direct writing (LDW) technique is one of the best candidates to fabricate plasmonic structure owing to its low cost, high throughput and simple experimental setup. Here, we fabricate the plasmonic structures to manipulate the scattering of SPP waves by LDW technique. Both the backward and forward scattering of surface plasmonic waves can be generated by the arranged gold (Au) nanobumps on an Au thin film. Upon controlling the geometry of the plasmonic structures, the height, position, and pattern of scattered light are modified as desired. It provides a simple and efficient way to project a specific light pattern into free space, and demonstrate the capability of three-dimensional light manipulation. Furthermore, we demonstrated that, with tightly contacted donor-receiver pair, multilayer plasmonic structures such as multilayer split resonant rings and square-shaped multilayer resonant cavities, can be fabricated on donor by laser-induced forward transfer (LIFT) process as a kind of LDW. By using the contact-mode LIFT, the illuminated materials of sputtered multilayer thin films are ablated and transferred to the receiver, which would leave the uniform metamolecules with multilayer structures on the donor. Finally, we have analyzed their plasmonic modes by both measurement and simulated results. These properties may facilitate many applications in integrated optics, optical nonlinearities, and luminescence enhancement, etc‥