Photoluminescence excitation spectroscopy on InP: Yb

Photoluminescence excitation measurements were performed on InP: Yb, using a tunable LiF: ${\mathrm{F}}_2^{+}$ colorcenter laser. The excitation spectra show that only one dominant ${\mathrm{Yb}}^{3+}$ ($4f^{13}$) center is responsible for the complex set of emission lines observed in the 1.0-μm spectral range. With the combination of the present results with data obtained by photoluminescence experiments the observed emission lines can be ordered into a level scheme with a twofold-split initial (${}_{}{}^2{}_{}{}^{}F_{\frac{5}{2}}^{}{}_{}{}^{}$) and a threefold-split (${}_{}{}^2{}_{}{}^{}F_{\frac{7}{2}}^{}{}_{}{}^{}$) ground state.