Characterization of Optical and Spin Properties of Single Tin-Vacancy Centers in Diamond Nanopillars

Abstract

Color centers in diamond have attracted much interest as candidates for optically active, solid-state quantum bits. Of particular interest are inversion-symmetric color centers based on group-IV impurities in diamond because they emit strongly into their zero-phonon lines and are insensitive to electric field noise to first order. Early studies of the negatively-charged tin-vacancy (SnV${}^{-}$) center in diamond have found the SnV${}^{-}$ to be a promising candidate: it has high quantum efficiency, emits strongly into its zero-phonon lines, and is expected to have a long $T_2$ spin coherence time at 4~K. To develop the SnV${}^{-}$ into a spin qubit requires further characterization, especially of the spin and optical properties of individual SnV${}^{-}$ in nanofabricated structures. In this work we isolate single SnV${}^{-}$ centers in diamond nanopillars and characterize their emission properties and their spin response to a magnetic field. We observe narrow emission linewidths that are spectrometer-limited, as well as a strong polarization dependence of each transition. We also find the Zeeman splitting under a magnetic field to be in good agreement with theoretical prediction. Our results pave the way toward future employment of single SnV${}^{-}$s for optically accessible quantum memories.

10 pages, 4 figures