We report the observation of cw four-wave mixing and phase conjugation in the UV on the N3 color-center resonance in diamond. Using a jitter-free technique, the nearly degenerate four-wave mixing spectrum has been measured and the ultranarrow, 250-Hz-wide resonance analyzed to understand the metastable-state decay process responsible for the low quantum efficiency and large nonlinear susceptibility of this aggregated nitrogen structure. The results establish the existence and lifetime of a new excited state of the defect.We report the observation of cw four-wave mixing and phase conjugation in the UV on the N3 color-center resonance in diamond. Using a jitter-free technique, the nearly degenerate four-wave mixing spectrum has been measured and the ultranarrow, 250-Hz-wide resonance analyzed to understand the metastable-state decay process responsible for the low quantum efficiency and large nonlinear susceptibility of this aggregated nitrogen structure. The results establish the existence and lifetime of a new excited state of the defect.

Optics LettersFeb 1, 19885 citations

Generation and spectroscopy of atoms and molecules in metastable states

Matthias Raunhardt

Jan 1, 20090 citations

Ultranarrow Nonlinear Optical Resonances in Solids

Duncan G. Steel, Stephen Colby Rand

Using a method for nonlinear laser spectroscopy which eliminates the effects of laser jitter in nearly degenerate four-wave mixing, we present the first direct measurement of the ground-state relaxation rate of optically excited ${\mathrm{Cr}}^{3+}$ ions in Cr: YAl ${\mathrm{O}}_{3}$ . The Lorentzian linewidth of the emission resonance is 9.8 Hz (FWHM). The mechanism of ground-state relaxation is established to be fluorescent decay of the $^{2}E$ metastable level.Using a method for nonlinear laser spectroscopy which eliminates the effects of laser jitter in nearly degenerate four-wave mixing, we present the first direct measurement of the ground-state relaxation rate of optically excited ${\mathrm{Cr}}^{3+}$ ions in Cr: YAl${\mathrm{O}}_{3}$. The Lorentzian linewidth of the emission resonance is 9.8 Hz (FWHM). The mechanism of ground-state relaxation is established to be fluorescent decay of the $^{2}E$ metastable level.

Physical Review LettersNov 18, 198550 citations

{\mathrm{Cr}}^{3+}

ions in Cr: YAl

{\mathrm{O}}_{3}

. The Lorentzian linewidth of the emission resonance is 9.8 Hz (FWHM). The mechanism of ground-state relaxation is established to be fluorescent decay of the

^{2}E

metastable level.