Open AccessFormation of nanostructures and optical analogues of massless Dirac particles via femtosecond lasers
Author(s) -
Nan Zhang,
ShihChi Chen
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.403336
Subject(s) - nanolithography , femtosecond , nanostructure , conical surface , surface plasmon polariton , materials science , plasmon , surface plasmon , laser , optoelectronics , optics , nanophotonics , optical tweezers , nanotechnology , physics , medicine , alternative medicine , pathology , fabrication , composite material
Subwavelength-scale surface structures have many important engineering and nanotechnology applications, e.g., superhydrophobicity and light-trapping. However, an effective and economic nanofabrication solution for general engineering materials, e.g., metals or silicon, is still not available to date. In this paper, we present an experimental and theoretical study of the nanostructure formation mechanism based on double time-delayed femtosecond laser beams and the coupled mode theory (CMT), demonstrating the use of an optical analogue of massless Dirac particles for high-throughput nanofabrication for the first time. In the experiments, a variety of complex periodic structures, including hexagonally arranged nanoholes, nano-square array, and periodic ripples, have been fabricated. The formation mechanisms of these nanostructures are explained by the CMT, where a transient plasmonic waveguide array (TPWA) is formed by the interference between the preceding laser and the induced surface plasmon polaritons (SPPs). The SPPs induced by the subsequent laser propagates through the TPWA, resulting in conical diffraction. This result shows the first practical application of the massless Dirac dynamics in nanofabrication.