A new antenna design boosts microwave fields for quantum sensors

Achieving a uniform and intense magnetic field is critical for microsensing, yet current antenna designs struggle to balance field strength, bandwidth, and compactness. Researchers report a new planar antenna capable of generating a nearly uniform magnetic field of 1-10 Gauss across a wide frequency range of 100 MHz-100 GHz within a thin layer of material. This design utilizes two thin, parallel metal electrodes as a spacer for a paramagnetic medium, maintaining full optical accessibility for techniques like optically detected magnetic resonance (ODMR). The antenna addresses key problems including achieving uniform fields, optimizing bandwidth, and managing power consumption, all while maintaining optical access. Generating a 1-10 Gauss magnetic field with…