| Abstract Scope |
Inductors are conductors conventionally in the form of metal coils. Coil-less inductors are feasible, due to the material microstructure/nanostructure, which can cause current path tortuosity and govern the inductance. The inductance that has been reported for inductors in general is the volumetric inductance, i.e., the inductance due to the entire volume of the material or coil. This work introduces the surface inductance, which is the inductance of the surface region (e.g., 6-nm thickness), as measured using electrodes on the same surface. Compared to the surface inductance, the surface resistance is less sensitive to current path tortuosity and the electrode quality is more demanding. The surface inductance is above the volumetric inductance by orders of magnitude, due to the limited surface current penetration and the volume amounting effectively to inductors in parallel, thereby decreasing the inductance. This method has been applied to graphite, carbon fiber, aluminum, and 3D-printed conductive polymer-based composites. |