Observation of bandgap guidance of optical vortices in a tunable negative defect.
We experimentally demonstrate linear bandgap guidance of optical vortices as high-gap defect modes (DMs) in two-dimensional induced photonic lattices. We show that donut-shaped vortex beams can be guided in a tunable negative (lower-index) defect, provided that the defect strength is set at an appropriate level. Such vortex DMs have fine features in the "tails" associated with the lattice anisotropy and can be considered as a superposition of dipole DMs. Our numerical results find good agreement with experimental observations.
Song
Daohong
D
Key Laboratory of Weak-Light Nonlinear Photonics, Ministry of Education and TEDA Applied Physics School, Nankai University, Tianjin 300457, China.
Wang
Xiaosheng
X
Shuldman
Daniel
D
Wang
Jiandong
J
Tang
Liqin
L
Lou
Cibo
C
Xu
Jingjun
J
Yang
Jianke
J
Chen
Zhigang
Z