Efficient Photonic Integration of Diamond Color Centers and Thin-Film Lithium Niobate

On-chip photonic quantum circuits with integrated quantum memories have the potential to radically progress hardware for quantum information processing. In particular, negatively charged group-IV color centers in diamond are promising candidates for quantum memories, as they combine long storage times with excellent optical emission properties and an optically-addressable spin state. However, as a material, diamond lacks many functionalities needed to realize scalable quantum systems. Thin-film lithium niobate (TFLN), in contrast, offers a number of useful photonic nonlinearities, including the electro-optic effect, piezoelectricity, and capabilities for periodically-poled quasi-phase matching. Here, we present highly efficient heterogeneous integration of diamond nanobeams containing negatively charged silicon-vacancy (SiV) centers with TFLN waveguides. We observe greater than 90\% transmission efficiency between the diamond nanobeam and TFLN waveguide on average across multiple measurements. By comparing saturation signal levels between confocal and integrated collection, we determine a $10$-fold increase in photon counts channeled into TFLN waveguides versus that into out-of-plane collection channels. Our results constitute a key step for creating scalable integrated quantum photonic circuits that leverage the advantages of both diamond and TFLN materials

On the Intrinsic Fracture Pressure of Liquid and Solid Aluminum Around Its Melting Temperature

To determine the intrinsic fracture pressure of aluminum, data from studies that have used molecular dynamic simulations, the van der Waals method as well as experimental observations have been gathered and analyzed. Results indicate that aluminum has an intrinsic fracture pressure of − 4 GPa at its melting temperature in both liquid and solid states. Moreover, the Fisher equation can be used to estimate the intrinsic fracture pressure of liquid aluminum