Manipulating the topological property of iso-frequency contour (IFC) will provide a unique control for the interaction between light and matter, such as increased rates of spontaneous emission and negative refraction. Different from the aforementioned topological transition that is realized by controlling the in-plane anisotropic electromagnetic parameters in a two-dimensional case, we theoretically propose and experimentally demonstrate another topological transition by tuning the vertical electromagnetic parameters of the anisotropic medium. Specially, the critical IFC in this transition corresponds to two intersecting lines and can be called linear-crossing metamaterial (LCMM). Based on the directional propagation and negative refraction in LCMM, we demonstrate the focusing and super-resolution with partial cloaking in transmission-line-based LCMMs. The realization of LCMM will open up another avenue for controlling light propagation and verifying unusual phenomena involving zero-index media and hyperbolic metamaterials.

• Received 4 September 2018
• Revised 2 November 2018

DOI:https://doi.org/10.1103/PhysRevApplied.10.064048