An Electronically Reconfigurable Magnetic Metasurface for Low-Frequency RF Applications

This paper delves into electronically reconfigurable, low-frequency magnetic metasurfaces, a cutting-edge domain that promises a paradigm shift in the field of electromagnetic engineering. In particular, this work introduces a novel concept of an electronically reconfigurable 3× 3 magnetic metasurface excited by an active RF coil placed in its near-field region and operating at 3 MHz. Reconfigurability is achieved by incorporating a varactor diode on each unit-cell of the metasurface. Experimental measurements were conducted over a fabricated prototype, in which two different unit-cells currents patterns are shown. The dynamic nature of the structure enables easy switching between different configurations in real-time, hence facilitating a wide range of applications including wireless power transfer, sensing, and MRI enhancement.