The molecular structure of a 3d 5 configuration ion in a trigonal ligand field is theoretically established on the basis of the 252\times252 complete energy matrice. The optical absorption and the electron paramagnetic resonance spectra of the Fe3+ ion in the sapphire crystal (α-Al2 O3) have been studied by diagonalizing the complete energy matrice. The calculated results are in very good agreement with previous experimental observations. The strength of the transition probabilities between pairs of the energy levels have been calculated to determine the possibility to achieve a population inversion in the ground state by applying optical pumping to the crystal. Preliminary results based on the computed transition parameters and on the maser rate equations model show that a 31 GHz maser signal can be effectively generated depending on the cryogenic resonator design.The molecular structure of a 3d 5 configuration ion in a trigonal ligand field is theoretically established on the basis of the 252\times252 complete energy matrice. The optical absorption and the electron paramagnetic resonance spectra of the Fe3+ ion in the sapphire crystal (α-Al2 O3) have been studied by diagonalizing the complete energy matrice. The calculated results are in very good agreement with previous experimental observations. The strength of the transition probabilities between pairs of the energy levels have been calculated to determine the possibility to achieve a population inversion in the ground state by applying optical pumping to the crystal. Preliminary results based on the computed transition parameters and on the maser rate equations model show that a 31 GHz maser signal can be effectively generated depending on the cryogenic resonator design.

arXiv:1201.1760Jan 9, 20120 citations

Measurement of g⊥ of Optically Excited State \barE (2E) of Cr3+ in Al2O3

孝夫村本, Yukio Fukuda, Tsuneo Hashi

Journal of the Physical Society of JapanJun 1, 196913 citations

Cooperative Absorption and Luminescence in Cr3+ -Doped EuAl O3

Jan P. van der Ziel, LeGrand G. Van Uitert

Absorption and emission involving exchange-coupled nearest-neighbor ${\mathrm{Cr}}^{3+}$ and ${\mathrm{Eu}}^{3+}$ ions have been observed in ${\mathrm{Cr}}^{3+}$ -doped EuAl ${\mathrm{O}}_{3}$ at the sum of the chromium $^{2}E_{g}$ and europium $^{7}F_{1}$ energies. Weak absorption at the difference energy has also been observed. The latter is the inverse of the previously studied europium terminated chromium emission. The intensities of the ${\mathrm{Eu}}^{3+}$ sideband transitions vary with the strength of the exchange-induced electric dipole moment.Absorption and emission involving exchange-coupled nearest-neighbor ${\mathrm{Cr}}^{3+}$ and ${\mathrm{Eu}}^{3+}$ ions have been observed in ${\mathrm{Cr}}^{3+}$-doped EuAl${\mathrm{O}}_{3}$ at the sum of the chromium $^{2}E_{g}$ and europium $^{7}F_{1}$ energies. Weak absorption at the difference energy has also been observed. The latter is the inverse of the previously studied europium terminated chromium emission. The intensities of the ${\mathrm{Eu}}^{3+}$ sideband transitions vary with the strength of the exchange-induced electric dipole moment.

Physical review. B, Solid stateSep 1, 197313 citations

Absorption and emission involving exchange-coupled nearest-neighbor

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

and

{\mathrm{Eu}}^{3+}

ions have been observed in

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

-doped EuAl

{\mathrm{O}}_{3}

at the sum of the chromium

^{2}E_{g}

and europium

^{7}F_{1}

energies. Weak absorption at the difference energy has also been observed. The latter is the inverse of the previously studied europium terminated chromium emission. The intensities of the

{\mathrm{Eu}}^{3+}

sideband transitions vary with the strength of the exchange-induced electric dipole moment.