Invisibility concentrator based on van der Waals semiconductor α-MoO.

By combining transformation optics and van der Waals layered materials, an invisibility concentrator with a thin layer of α-MoO wrapping around a cylinder is proposed. It inherits the effects of invisibility and energy concentration at Fabry-Pérot resonance frequencies, with tiny scattering. Due to the natural in-plane hyperbolicity in α-MoO, the challenges of experimental complexity and infinite dielectric constant can be resolved perfectly. Through analytical calculation and numerical simulations, the relevant functionalities including invisibility, energy concentration and illusion effect of the designed device are confirmed, which provides guidelines for the subsequent experimental verification in future.