Large spatial shifts of a reflected Airy beam on thesurface of hyperbolic crystals

The large Goos–Hänchen (GH) and Imbert–Fedorov (IF) shifts of a reflective Airy beam impinging upon the surface of hyperbolic crystals are theoretically investigated. These two typical models, incident by the linearly polarized Airy beam, are discussed, where the optical axis is parallel or vertical to the incident plane, respectively. Compared with the Gaussian or vortex beam, the GH and IF shifts caused by Airy beams are increased by at least two orders of magnitude in or near the reststrahlen bands of hexagonal boron nitride (hBN), especially in the vicinity of epsilon-near-zero. The conditions improving the GH and IF shifts are deeply examined, which are determined by the permittivity and thickness of hBN and the incident frequency, respectively. For the arbitrary orientation of the optical axis, it has been demonstrated that the left-circularly polarized Airy beam has to be used to generate the large spatial shifts at a certain incident angle and frequency. These results may provide a feasible way to obtain great spatial shifts and be applied in infrared optical detection.