Color centers based on heavy group-IV elements

Abstract

Color centers in diamond are a promising platform for quantum information processing and quantum network applications. Color centers using group-IV elements with an inversion symmetry possess very sharp zero phonon lines and stable emission, which can solve issues on the optical properties of a nitrogen-vacancy center. Especially, here, we show the properties of heavy group-IV color centers using germanium, tin, and lead. In addition to the optical properties, we discuss the spin properties of the group-IV color centers from the orbital relaxation rate to spin coherence time, and show that the heavier group-IV elements have a possibility to achieve a long spin coherence time at higher temperatures, compared with a silicon-vacancy center. In this chapter, we introduce the basics (structure and fabrication methods), optical properties, spin properties, and nanophotonic integration of the heavy group-IV color centers.