Open AccessTransient establishment of the wavefronts for negative, zero, and positive refraction
Author(s) -
Wenjuan Zhao,
Qiang Wu,
Ride Wang,
Jianshun Gao,
Yao Lu,
Qi Zhang,
Jiwei Qi,
Chunyu Zhang,
Chongpei Pan,
Romano A Rupp,
Jingyi Xu
Publication year - 2018
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.26.001954
Subject(s) - negative refraction , refraction , wavefront , optics , physics , refractive index , wedge (geometry) , superluminal motion , metamaterial , phase (matter) , phase velocity , quantum mechanics , astronomy
We quantitatively demonstrate transient establishment of wavefronts for negative, zero, and positive refraction through a wedge-shaped metamaterial consisting of periodically arranged split-ring resonators and metallic wires. The wavefronts for the three types of refractions propagate through the second interface of the wedge along positive refraction angles at first, then reorganize, and finally propagate along the effective refraction angles after a period of establishment time respectively. The establishment time of the wavefronts prevents violating causality or superluminal propagation for negative and zero refraction. The establishment time for negative or zero refraction is longer than that for positive refraction. For all three refraction processes, transient establishment processes precede the establishment of steady propagation. Moreover, some detailed characters are proven in our research, including infinite wavelength, uniform phase inside the zero-index material, and the phase velocity being antiparallel to the group velocity in the negative-index material.