English

Negative refraction in hyperbolic hetero-bicrystals

Mesoscale and Nanoscale Physics 2023-07-10 v7

Abstract

We visualized negative refraction of phonon polaritons, which occurs at the interface between two natural crystals. The polaritons - hybrids of infrared photons and lattice vibrations - form collimated rays that display negative refraction when passing through a planar interface between the two hyperbolic van der Waals materials: molybdenum oxide (MoO3MoO_3) and isotopically pure hexagonal boron nitride (h11BNh^{11}BN). At a special frequency ω0\omega_0, these rays can circulate along closed diamond-shaped trajectories. We have shown that polariton eigenmodes display regions of both positive and negative dispersion interrupted by multiple gaps that result from polaritonic level repulsion and strong coupling.

Keywords

Cite

@article{arxiv.2209.15155,
  title  = {Negative refraction in hyperbolic hetero-bicrystals},
  author = {A. J. Sternbach and S. L. Moore and A. Rikhter and S. Zhang and R. Jing and Y. Shao and B. S. Y. Kim and S. Xu and S. Liu and J. H. Edgar and A. Rubio and C. Dean and J. Hone and M. M. Fogler and D. N. Basov},
  journal= {arXiv preprint arXiv:2209.15155},
  year   = {2023}
}
R2 v1 2026-06-28T02:25:11.828Z