Optimized Quantum Photonics in Diamond*

Diamond hosts a variety of quantum emitters and is thus a promising material platform for applications in quantum information processing and quantum sensing. Such quantum technologies will likely operate at the level of single or few photons. Therefore, they require highly efficient integrated photonic circuits to harness the full potential of the excellent optical properties of color centers in diamond. However, state-of-the-art design and fabrication techniques for diamond devices in quantum optics strongly limit the geometry and variety of the device components. We utilize inverse design optimization and fabrication methods based on quasi-isotropic etching to significantly improve on efficiency, scalability, and functionality of diamond photonics. To showcase the significance of these advances, we solve outstanding design challenges, such as optical free space interfaces and improve on efficiency and scalability of diamond photonics.