The vast majority of magnetometers are a variation on coil magnetometers. And no, rotating coil magnetometer aren't the only ones. Quantum radar is not affecte

The vast majority of magnetometers are a variation on coil magnetometers. And no, rotating coil magnetometer aren't the only ones. Quantum radar is not affected by the sun, it doesn't operate in the same wavelength. As for how far we are at decoherence issues, neither of us can know. The state of the art is assuredly massively classified.