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The transmission properties of disordered photonic graphenes are investigated in microwave experiments. In the weak-localization regime, we found that, in the passbands the transmission decreases as the random degree increases, owing to the enhanced coherent backscattering effect. However, at the Dirac point, with the increase of the random degree, the transmission increases rather than decreasing. This observed anomalous transportation, also called weak antilocalization, provides the important experimental clue that the Berry phase associated with the Dirac point may suppress the coherent backscattering effect in a random system.

In this letter, a potential way to transfer power wirelessly based on magnetic metamaterials (MMs) assembled by ultra-subwavelength meta-atoms is proposed. Frequency-domain simulation and experiments are performed for accurately obtaining effective permeability of magnetic metamaterials. The results demonstrate that MMs possess great power for enhancing the wireless power transfer efficiency between two non-resonant coils. Further investigations on the magnetic-field distribution demonstrate that a large-area flattened magnetic field in near range can be effectively realized, exhibiting great flexibility in assembling.

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Recently, it has been theoretically shown that anisotropic metamaterials with a near-zero index can flexibly control electromagnetic flux in the subwavelength scale. Here, by using two-dimensional transmission lines with lumped elements, we design and fabricate a type of anisotropic metamaterial with a near-zero permeability component. By further introducing spatial variations into the system, we experimentally realize the subwavelength flux manipulation in such a highly anisotropic environment, which is conducted via evanescent scattered waves. The experimental results agree well with the simulation. Our work verifies the feasibility of subwavelength flux manipulation in near-zero index materials.