Open AccessBand evolution and Landau-Zener Bloch oscillations in strained photonic rhombic lattices
Author(s) -
Shiqiang Xia,
Yingying Zhang,
Zhixiang Li,
Lu Chang Qin,
Chun-Jie Yang,
Hai Lu,
Jun Zhang,
Xing-Dong Zhao,
Zunlue Zhu
Publication year - 2021
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.441554
Subject(s) - condensed matter physics , bloch oscillations , zener diode , physics , photonic crystal , symmetry (geometry) , quantum tunnelling , electronic band structure , band gap , quantum mechanics , superlattice , geometry , mathematics , voltage , resistor
We investigate band evolution of chiral and non-chiral symmetric flatband photonic rhombic lattices by applying a strain along the diagonal direction, and thereby demonstrating Landau-Zener Bloch (LZB) oscillations in the presence of a refractive index gradient. The chiral and non-chiral symmetric rhombic lattices are obtained by adding a detuning to uniform lattices. For the chiral symmetric lattices, the middle flatband is perturbed due to the chiral symmetry breaking while a nearly flatband appears as the bottom band with the increase of strain-induced next-nearest-neighbor hopping. Consequently, LZB oscillations exhibit intriguing characteristics such as asymmetric energy transitions and almost complete suppression of the oscillations. Nevertheless, for the non-chiral symmetric lattices, flatband persists owing to the retained particle-hole symmetry and evolves into the bottom band. Remarkably, the band gap can be readily tuned, which allows controlling of the amplitude of Landau-Zener tunneling (LZT) rate and may lead to thorough LZT. Our analysis provides an alternative perspective on the generation of tunable flatband and may also bring insight to study the symmetry and topological characterization of the flatband.