In certain examples, methods and semiconductor structures are directed to an apparatus including source circuitry configured to provide power to other circuitry, with the source circuitry including amplification circuitry (e.g., with a power-switching output) and a source resonator. The amplification circuitry is to provide power to the source resonator with a gain that is dependent on a coupling rate between the source circuitry and other external-receiving circuitry. The source circuitry is also to offset phase delay caused by the amplifier. In operation, the source resonator generates a magnetic field in response to the power, for highly-efficient wirelessly transfer of the power to the other circuitry.