Abstract: A magnetometer for magnetic detection includes a magneto-optical defect center material including at least one magneto-optical defect center that emits an optical signal when excited by an excitation light, a radio frequency (RF) exciter system configured to provide RF excitation to the magneto-optical defect center material, an optical excitation system configured to direct the excitation light to the magneto-optical defect center material, an optical detector configured to receive the optical signal emitted by the magneto-optical defect center material based on the excitation light and the RF excitation, and a magnetic field generator configured to generate a magnetic field detected at the magneto-optical defect center material, the magnetic field generator including a plurality of permanent magnets arranged in a Halbach array.