Disorder effects of nitrogen impurities, irradiation-induced defects, and 13C isotope composition on the Raman spectrum in synthetic Ib diamond

Optical Properties of Bulk Single-Crystal Diamonds at 80-1200 K by Vibrational Spectroscopic Methods

Bulk diamonds show great potential for optical applications such as for use in infrared (IR) windows and temperature sensors. The development of optical-grade bulk diamond synthesis techniques has facilitated its extreme applications. Here, two kinds of bulk single-crystal diamonds, a high-pressure and high-temperature (HPHT) diamond and a chemical vapor deposition (CVD) diamond, were evaluated by Raman spectroscopy and Fourier Transform Infra-Red (FTIR) spectroscopy at a range of temperatures from 80 to 1200 K. The results showed that there was no obvious difference between the HPHT diamond and the CVD diamond in terms of XRD and Raman spectroscopy at 300-1200 K. The measured nitrogen content was ~270 and ~0.89 ppm for the HPHT diamond and the CVD diamond, respectively. The moderate nitrogen impurities did not significantly affect the temperature dependence of Raman spectra for temperature-sensing applications. However, the nitrogen impurities greatly influence FTIR spectroscopy and optical transmittance. The CVD diamond showed higher transmittance, up to 71% with only a ~6% drop at temperatures as high as 873 K. This study shows that CVD bulk diamonds can be used for IR windows under harsh environments.

Diamond nanostructures: isotopes for nanoelectronic devices

Charge carriers have been confined by exploiting the small difference between the bandgap energies of the two naturally occurring stable isotopes of carbon.

Stable solid-state source of single photons

Fluorescence light observed from a single nitrogen-vacancy center in diamond exhibits strong photon antibunching: The measured pair correlation function g((2))(0) shows that only one photon is emitted at a time. Nitrogen-vacancy centers are well localized, stable against photobleaching even at room temperature, and can be addressed in simple experimental configurations.

13C NMR Investigations of Spin-Lattice Relaxation in 99% 13C-Enriched Diamonds

The paper is devoted to investigations of spin-lattice relaxation processes in 99% 13C-enriched diamonds. Relaxation time measurements were performed as a function of orientation, magnetic field, and temperature. Both experimental results and theoretical discussion are presented. Multiexponential behavior of nuclear magnetization recovery was observed. There was found no significant influence of the diamond orientation on the nuclear spin-lattice relaxation. The field dependence of the spin-lattice relaxation time was found to be proportional to the second power of the magnetic field. The temperature measurements showed a weak increase of the spin-lattice relaxation time with decreasing temperature. Possible mechanisms of impurity relaxation are considered and compared with the experimental data. Copyright 1998 Academic Press. Copyright 1998 Academic Press