Germanium-vacancy center in diamond

The germanium-vacancy center (Ge-V) is an optically active defect in diamond, which can be created by doping germanium into diamond during its growth or by implanting germanium ions into diamond after its growth. Its properties are similar to those of the silicon-vacancy center in diamond (SiV). Ge-V can behave as a single-photon source and shows potential for quantum and nanoscience applications due to its narrow zero-phonon line (ZPL) and minimal phononic-sideband (compared to that of the nitrogen-vacancy center (NV)).[1]

The semi-divacancy model of the Ge-V center, which is also common for other large impurities in diamond.
Ge-V luminescence spectra measured at different temperatures.[1]
Spatial map of Ge-V centers in diamond produced by ion implantation.[1]

Properties edit

Ge-V is predicted to consist of one germanium atom situated between two adjacent lattice vacancies and have the same D3d point group symmetry as SiV. It has a single ZPL at 602 nm (2.059 eV) at room-temperature, which splits into two components separated by 0.67 meV at low-temperatures (10 K). The Ge-V has an excited state lifetime of 1.4–5.5 ns.[1]

Formation edit

Ge-V can be created during the diamond growth, or by ion implantation and subsequent annealing at 800 °C. The former way results in lower lattice strain, as revealed by the spread in the position and width of the Ge-V ZPL.[1][2]

References edit

  1. ^ a b c d e Iwasaki, T.; Ishibashi, F.; Miyamoto, Y.; Doi, Y.; Kobayashi, S.; Miyazaki, T.; Tahara, K.; Jahnke, K. D.; Rogers, L. J.; Naydenov, B.; Jelezko, F.; Yamasaki, S.; Nagamachi, S.; Inubushi, T.; Mizuochi, N.; Hatano, M. (2015). "Germanium-Vacancy Single Color Centers in Diamond". Scientific Reports. 5: 12882. arXiv:1503.04938. Bibcode:2015NatSR...512882I. doi:10.1038/srep12882. PMC 4528202. PMID 26250337.
  2. ^ Palyanov, Y. N.; Kupriyanov, I. N.; Borzdov, Y. M.; Surovtsev, N. V. (2015). "Germanium: a new catalyst for diamond synthesis and a new optically active impurity in diamond". Scientific Reports. 5: 14789. Bibcode:2015NatSR...514789P. doi:10.1038/srep14789. PMC 4593174. PMID 26435400.