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Two-beam coupling by nitrogen-vacancy centers in diamond.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Redman, David Shu, Q. Q. Lenef, Alan L. Rand, Stephen |
| Copyright Year | 1992 |
| Abstract | Intersecting laser beams with finite detuning are typically used to generate slowly moving optical gratings in absorptive solids with phases that lead those of refractive-index changes caused by slow excited-state dynamics. Energy transfer between pump and probe waves then occurs, with detuningdependent gain. This method has been employed to study nonlinearities in Cr-doped laser materials2 with simple impurity energy levels and hostdependent nonlinearities of relevance to high-power tunable Cr-laser performance. Here we introduce a method that furnishes twobeam coupling spectra versus detuning in seconds, and we use it to study simple impurity centers in diamond. With it, relaxation processes of the nitrogen-vacancy (N-V) color center, for which the energy-level structure was determined only recently,3 are characterized. By extending two-beam coupling theory to incorporate two separate decay processes contributing to saturation, we obtain good agreement between complex changes in signal intensity and detuning, as well as consistency with earlier determinations of N-V relaxation times. We also report estimates of real and imaginary parts of the nonlinear index. The N-V center consists of a N-V complex in diamond, 4 one of many point defects5 that need to be characterized carefully to evaluate potential applications' of this emerging wide-gap semiconductor. The electronic structure 3 and absorption spectrum of the center are shown in Fig. 1(a). As indicated by three-pulse photon echo data in Fig. 1(b), the 3E state decays rapidly in 13.3 ± 0.2 ns, revealing that this decay channel cannot contribute to optical saturation at low intensities. 6 However, intersystem crossing from the 'A to the ground state (r = 265 ms) and the spin-lattice relaxation between the 3A ground-state components (X = 1.17 ms) are extremely slow. 3 Hence in the N-V center we expect two physically distinct processes to contribute to low-intensity saturation behavior at wavelengths near the first resonance, unlike the singlesusceptibility due to intersystem crossing and spin- |
| Starting Page | 184 |
| Ending Page | 188 |
| Page Count | 5 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://web.eecs.umich.edu/faculty/rand/papers/OLShu1992.pdf |
| Alternate Webpage(s) | http://www.eecs.umich.edu/~scr/OLShu1992.pdf |
| PubMed reference number | 19784266v1 |
| Volume Number | 17 |
| Issue Number | 3 |
| Journal | Optics letters |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Adjudication Blood urea nitrogen measurement Chromium Contribution Diamond Estimated Photons Semiconductors solid substance wavelength |
| Content Type | Text |
| Resource Type | Article |
