Near-field planar antenna for microwave excitation of paramagnetic quantum emitters

The concept of a microwave planar antenna for the excitation of dielectric paramagnetic media is proposed. The shape and size of the electrodes are designed for the generation of a uniform magnetic field parallel to the surfaces of a single- or multilayer dielectric, with a specific resonance frequency and bandwidth. One or both electrodes can be semireflective to allow the optical accessibility of the paramagnetic media and, possibly, to enhance the collection efficiency by beaming the optical emission of quantum emitters. This device is particularly useful in optically detected magnetic resonance due to the large bandwidth of the microwave excitation and favorable conditions for optical excitation and detection. Applications are devised especially in vector magnetometry and microwave spectral analysis because of the paramagnetic quantum properties of emitters such as the nitrogen-vacancy center in diamond.