Placing Single Impurities into a Crystal

Solid-state materials that contain specific impurities, such as nitrogen-vacancy centers in diamond, make promising platforms for future quantum information technologies. The quantum states of the impurities can be tailored to perform quantum logic operations, and these states can then be read out via the impurities’ fluorescence. However, implanting single-ion impurities inside crystals consistently and precisely has proved challenging. Current methods involve accelerating the ions to high energies, which allows detection of the implantation events but sacrifices spatial precision. A new implantation technique takes a step towards solving this problem. A team from Johannes Gutenberg University Mainz demonstrated that they could embed ions in a crystal at low energy to form patterns reliably and with nanometer-scale precision.