RESUMO
The concept of multifunctional transformation-dc devices is proposed and verified experimentally. The functions of dc metamaterials can be remotely altered by illuminating with visible light. If the light-induced dc illusion effect is activated, the electrostatic behavior of the original object is perceived as multiple equivalent objects with different pre-designed geometries. The experimental verification of the functional device makes it possible to control sophisticated transformation-dc devices with external light illumination.
RESUMO
We investigate a dc electric concentrator for steady current fields theoretically and experimentally. Based on the transformation electrostatics, we show that the dc concentrator can focus electric currents into the central concentrated region and enhance the electric field and current density. Outside the concentrator, the current lines are distributed as the same as those in a homogeneous conducting material. Hence, such a dc electric concentrator has no impact on other external devices. Using the analogy between electrically conducting materials and resistor networks, we design, fabricate, and test a dc concentrator using the circuit theory. The measured results agree very well with the theoretical predictions and numerical simulations, demonstrating the perfect concentrating performance.