Intensity-dependent optical dephasing is shown to arise from nonresonant excitation of 1% ${\mathrm{Pr}}^{3+}$ -doped yttrium aluminum garnet (YAG) with UV radiation between 325--355 nm. UV irradiation of the sample with intensities greater than 30 MW/ ${\mathrm{cm}}^{2}$ produces persistent changes in the optical dephasing. Two-pulse photon echo decays on the $^{3}$ ${\mathit{H}}_{4}$ ${\ensuremath{\rightarrow}}^{1}$ ${\mathit{D}}_{2}$ transition of ${\mathrm{Pr}}^{3+}$ were measured at 1.5 K before and after exposure to UV radiation. Changes persisting for at least several hours are observed in the echo intensity, echo decay rate, and temporal form of the echo decay. Changes persist if the sample is kept below 10 K, but warming to 77 K results in the echo decays resuming their initial intensity and duration. No change is detected in the optical absorption spectrum of the ${\mathrm{Pr}}^{3+}$ ions after UV exposure, indicating that most of the ions remain in that charge state. Although the mechanism giving rise to the increased optical dephasing is not completely understood, the additional dynamics may arise from the UV radiation freeing electrons that become trapped in lattice defects. The presence of the dephasing at low temperatures indicates the availability of low-energy excitations of the electronic system.Intensity-dependent optical dephasing is shown to arise from nonresonant excitation of 1% ${\mathrm{Pr}}^{3+}$-doped yttrium aluminum garnet (YAG) with UV radiation between 325--355 nm. UV irradiation of the sample with intensities greater than 30 MW/${\mathrm{cm}}^{2}$ produces persistent changes in the optical dephasing. Two-pulse photon echo decays on the $^{3}$${\mathit{H}}_{4}$${\ensuremath{\rightarrow}}^{1}$${\mathit{D}}_{2}$ transition of ${\mathrm{Pr}}^{3+}$ were measured at 1.5 K before and after exposure to UV radiation. Changes persisting for at least several hours are observed in the echo intensity, echo decay rate, and temporal form of the echo decay. Changes persist if the sample is kept below 10 K, but warming to 77 K results in the echo decays resuming their initial intensity and duration. No change is detected in the optical absorption spectrum of the ${\mathrm{Pr}}^{3+}$ ions after UV exposure, indicating that most of the ions remain in that charge state. Although the mechanism giving rise to the increased optical dephasing is not completely understood, the additional dynamics may arise from the UV radiation freeing electrons that become trapped in lattice defects. The presence of the dephasing at low temperatures indicates the availability of low-energy excitations of the electronic system.

Physical review. B, Condensed matterFeb 1, 19940 citations

Coherent Transients by Optical Phase Switching: Dephasing in La Cl3 : Pr3+

Azriel Z. Genack, David A. Weitz, R. M. Macfarlane +2 more

Physical Review LettersSep 22, 19800 citations

Intensity-dependent optical dephasing is shown to arise from nonresonant excitation of 1%

{\mathrm{Pr}}^{3+}

-doped yttrium aluminum garnet (YAG) with UV radiation between 325--355 nm. UV irradiation of the sample with intensities greater than 30 MW/

{\mathrm{cm}}^{2}

produces persistent changes in the optical dephasing. Two-pulse photon echo decays on the

^{3}

{\mathit{H}}_{4}

${\ensuremath{\rightarrow}}^{1}$

{\mathit{D}}_{2}

transition of

{\mathrm{Pr}}^{3+}

were measured at 1.5 K before and after exposure to UV radiation. Changes persisting for at least several hours are observed in the echo intensity, echo decay rate, and temporal form of the echo decay. Changes persist if the sample is kept below 10 K, but warming to 77 K results in the echo decays resuming their initial intensity and duration. No change is detected in the optical absorption spectrum of the

{\mathrm{Pr}}^{3+}

ions after UV exposure, indicating that most of the ions remain in that charge state. Although the mechanism giving rise to the increased optical dephasing is not completely understood, the additional dynamics may arise from the UV radiation freeing electrons that become trapped in lattice defects. The presence of the dephasing at low temperatures indicates the availability of low-energy excitations of the electronic system.