Physical review. B, Solid state

Multiphonon-assisted anti-Stokes and Stokes fluorescence of triply ionized rare-earth ions

Francois E. Auzel

Published Apr 1, 1976• 245 citations

Abstract

Experimental demonstration of multiphonon-assisted anti-Stokes and Stokes excitation of rare-earth ions (${R}^{3+}$) in different hosts, that is, in a weak-coupling ion-lattice interaction case, is obtained. An exponential behavior of excitation probabilities with respect to energy difference between excitation and electronic line is found, just as for multiphonon-assisted nonradiative decay and energy transfer. Exponential parameters ${\ensuremath{\alpha}}_{\mathrm{AS}}$ and ${\ensuremath{\alpha}}_{\mathrm{S}}$ for anti-Stokes and Stokes excitation are measured and linked to the Miyakawa-Dexter $\ensuremath{\alpha}$ parameter for decay, leading to estimates for Pekar-Huang-Rhys coupling parameter ${S}_{0}$ of about 0.04, in agreement with values obtained from one-phonon spectra or nonradiative-decay measurements. A semiempirical formula is deduced to obtain $\ensuremath{\alpha}$ from only one parameter, an effective phonon energy.

DOI: 10.1103/physrevb.13.2809

Related papers

Multiphonon-assisted anti-Stokes and Stokes fluorescence of triply ionized rare-earth ions

Francois E. Auzel

Journal of LuminescenceMar 1, 197614 citations

Chapter 8 Bulk Cooling Efficiency Measurements of Yb-Doped Fluoride Single Crystals and Energy Transfer–Assisted Anti-Stokes Cooling in Co-Doped Fluorides

Azzurra Volpi, Alberto Di Lieto, M. Tonelli

Pan Stanford Publishing eBooksAug 31, 20160 citations

Phonon sidebands (stokes and anti-stokes) in the optical spectra of rare earth atoms in rare gas matrices

K. Luchner, Hans Micklitz

Journal of LuminescenceJan 1, 19793 citations

Energy Transfer and Cooperative Optical Transitions in Rare-Earth Doped Inorganic Materials. I. Transition Probability Calculation

Takashi Kushida

Journal of the Physical Society of JapanMay 1, 1973288 citations

Coherent anti-Stokes Raman scattering in PrF3

K. P. Traar

Physical review. B, Condensed matterMar 1, 19874 citations

The Spectra of the Doubly and Triply Ionized Rare Earths

G. H. Dieke, H. M. Crosswhite

The present status of our knowledge of the structure of the spectra of the doubly and triply ionized spectra of the rare earths is derived partly from experimental data of the emission spectra of the free ions which provide the energy level scheme in great detail but are difficult and laborious to analyze. For the lower levels knowledge of the structure comes from the crystal absorption and fluoresence spectra. In all cases approximate theoretical calculations of the energies are essential.

Applied OpticsJul 1, 19631,115 citations

Physical review. B, Solid state

Multiphonon-assisted anti-Stokes and Stokes fluorescence of triply ionized rare-earth ions

Francois E. Auzel

Published Apr 1, 1976• 245 citations

Publisher

Abstract

Experimental demonstration of multiphonon-assisted anti-Stokes and Stokes excitation of rare-earth ions (

{R}^{3+}

) in different hosts, that is, in a weak-coupling ion-lattice interaction case, is obtained. An exponential behavior of excitation probabilities with respect to energy difference between excitation and electronic line is found, just as for multiphonon-assisted nonradiative decay and energy transfer. Exponential parameters

{\ensuremath{\alpha}}_{\mathrm{AS}}

and

{\ensuremath{\alpha}}_{\mathrm{S}}

for anti-Stokes and Stokes excitation are measured and linked to the Miyakawa-Dexter

\ensuremath{\alpha}

parameter for decay, leading to estimates for Pekar-Huang-Rhys coupling parameter

{S}_{0}

of about 0.04, in agreement with values obtained from one-phonon spectra or nonradiative-decay measurements. A semiempirical formula is deduced to obtain

\ensuremath{\alpha}

from only one parameter, an effective phonon energy.

DOI: 10.1103/physrevb.13.2809

Related papers

Multiphonon-assisted anti-Stokes and Stokes fluorescence of triply ionized rare-earth ions

Francois E. Auzel

Journal of LuminescenceMar 1, 197614 citations

Chapter 8 Bulk Cooling Efficiency Measurements of Yb-Doped Fluoride Single Crystals and Energy Transfer–Assisted Anti-Stokes Cooling in Co-Doped Fluorides

Azzurra Volpi, Alberto Di Lieto, M. Tonelli

To overcome the ETU-induced heating and realize efficient and enhanced laser cooling in Ho3+-doped solids, in Section 4.3, we will provide a modified excitation scheme based on ground-state absorption (GSA) of 5I8 Æ 5I7 at around 2.07 μm and ESA of 5I5 Æ 5F5 at around 2.28 μm. Compared with the conventional pumping scheme, the co-pumping scheme ameliorates the cooling performance significantly through alleviating the upconversion-quenching-induced heat [12], that is, the heat-producing 5I5 Ho3+ions are pumped to the 5F5 state by the laser at 2.28 μm. Fortunately, the 5F5 Ho3+ ions barely transit to the lower nearby state and tend to decay radiatively. Therefore, major heat produced in the conventional laser cooling of Ho3+-doped solids is avoided, and both cooling efficiency and cooling power density can be improved. In Section 4.4, we broaden the research domain of optical refrigeration to rare earth ion co-doped systems. Specifically, when Ho3+–Tm3+ co-doped YLiF4 crystals are pumped at around 2.07 μm, Ho3+ ions will populate at the 5I7 manifold. Meanwhile, Tm3+ ions will also be sensitized by absorbing energy transferred from 5I7 Ho3+ ions. Since the average energy of fluorescence photons generated by Tm3+3F4 Æ 3H6 radiative transitions is higher than that generated by Ho3+5I7 Æ 5I8 radiative transitions, energy transfer (ET) from Ho3+ to Tm3+ ions will induce annihilation of host phonons, and bring enhancement in both the cooling efficiency and the cooling power. Therefore, this cooling mechanism is referred next as energy transfer-enhanced laser cooling (ETLC) of solids [11]. 4.2 Conventional Laser Cooling of Holmium- The main upconversion process and the anti-Stokes fluorescence cooling (ASFC) processes of Ho3+-doped fluoride crystals are illustrated in Fig. 4.1. The ground-state (5I8) Ho3+ ions are pumped to the first excited state (5I7) with laser excitations of energy hν (solid red arrow on the left) and then relax thermally among the Stark levels in a timescale of picoseconds with host phonon absorption. Part of the Ho3+5I7 ions de-excite by emitting fluorescence photons of mean energy hν10 (solid blue arrow, ν10 > ν), which accounts for the ASFC process. The rest of the 5I7 Ho3+ ions de-excited and transfer their energy to the neighboring 5I7 Ho3+ ions, causing population accumulation at the third excited state (5I5) with host phonon absorption (solid green arrows). Comparison between the energy mismatch and the host phonon energy (for YLiF4 crystal host, ħω ≈ 450 cm-1) indicates that about two host phonons are annihilated for each ETU process (see Table 4.1).To overcome the ETU-induced heating and realize efficient and enhanced laser cooling in Ho3+-doped solids, in Section 4.3, we will provide a modified excitation scheme based on ground-state absorption (GSA) of 5I8 Æ 5I7 at around 2.07 μm and ESA of 5I5 Æ 5F5 at around 2.28 μm. Compared with the conventional pumping scheme, the co-pumping scheme ameliorates the cooling performance significantly through alleviating the upconversion-quenching-induced heat [12], that is, the heat-producing 5I5 Ho3+ions are pumped to the 5F5 state by the laser at 2.28 μm. Fortunately, the 5F5 Ho3+ ions barely transit to the lower nearby state and tend to decay radiatively. Therefore, major heat produced in the conventional laser cooling of Ho3+-doped solids is avoided, and both cooling efficiency and cooling power density can be improved. In Section 4.4, we broaden the research domain of optical refrigeration to rare earth ion co-doped systems. Specifically, when Ho3+–Tm3+ co-doped YLiF4 crystals are pumped at around 2.07 μm, Ho3+ ions will populate at the 5I7 manifold. Meanwhile, Tm3+ ions will also be sensitized by absorbing energy transferred from 5I7 Ho3+ ions. Since the average energy of fluorescence photons generated by Tm3+3F4 Æ 3H6 radiative transitions is higher than that generated by Ho3+5I7 Æ 5I8 radiative transitions, energy transfer (ET) from Ho3+ to Tm3+ ions will induce annihilation of host phonons, and bring enhancement in both the cooling efficiency and the cooling power. Therefore, this cooling mechanism is referred next as energy transfer-enhanced laser cooling (ETLC) of solids [11]. 4.2 Conventional Laser Cooling of Holmium- The main upconversion process and the anti-Stokes fluorescence cooling (ASFC) processes of Ho3+-doped fluoride crystals are illustrated in Fig. 4.1. The ground-state (5I8) Ho3+ ions are pumped to the first excited state (5I7) with laser excitations of energy hν (solid red arrow on the left) and then relax thermally among the Stark levels in a timescale of picoseconds with host phonon absorption. Part of the Ho3+5I7 ions de-excite by emitting fluorescence photons of mean energy hν10 (solid blue arrow, ν10 > ν), which accounts for the ASFC process. The rest of the 5I7 Ho3+ ions de-excited and transfer their energy to the neighboring 5I7 Ho3+ ions, causing population accumulation at the third excited state (5I5) with host phonon absorption (solid green arrows). Comparison between the energy mismatch and the host phonon energy (for YLiF4 crystal host, ħω ≈ 450 cm-1) indicates that about two host phonons are annihilated for each ETU process (see Table 4.1).

Pan Stanford Publishing eBooksAug 31, 20160 citations

Phonon sidebands (stokes and anti-stokes) in the optical spectra of rare earth atoms in rare gas matrices

K. Luchner, Hans Micklitz

Journal of LuminescenceJan 1, 19793 citations

Energy Transfer and Cooperative Optical Transitions in Rare-Earth Doped Inorganic Materials. I. Transition Probability Calculation

Takashi Kushida

Calculations made of the rates for several processes involving interactions between rare earth ions in crystals, such as resonance energy transfer, cooperative excitation transfer and cooperative optical transitions. These processes are assumed to originate from the electric multipole interactions between the ions concerned. A tensor operator method is employed in order to take account of the individual characters of the energy levels involved in the transition. Evaluation of the typical transition probability is also made on the lowest-order parity-allowed processes in nearest neighbour ions. The rates for the resonance transfer and cooperative transfer processes thus estimated are much smaller than those obtained by Miyakawa and Dexter.Calculations made of the rates for several processes involving interactions between rare earth ions in crystals, such as resonance energy transfer, cooperative excitation transfer and cooperative optical transitions. These processes are assumed to originate from the electric multipole interactions between the ions concerned. A tensor operator method is employed in order to take account of the individual characters of the energy levels involved in the transition. Evaluation of the typical transition probability is also made on the lowest-order parity-allowed processes in nearest neighbour ions. The rates for the resonance transfer and cooperative transfer processes thus estimated are much smaller than those obtained by Miyakawa and Dexter.

Journal of the Physical Society of JapanMay 1, 1973288 citations

Coherent anti-Stokes Raman scattering in PrF3

K. P. Traar

I report the observation of Raman resonances due to the $^{3}\mathrm{H}_{4}$ ${\ensuremath{\rightarrow}}^{3}$ ${\mathrm{F}}_{2}$ transition in ${\mathrm{Pr}}^{3+}$ ions by coherent anti-Stokes Raman scattering. The very weak resonances could only be measured in ${\mathrm{PrF}}_{3}$ under cryogenic conditions (2 K). The ratio C=\ensuremath{\Vert}${\ensuremath{\chi}}^{(3)R}$/${\ensuremath{\chi}}^{(3)\mathrm{NR}}$${\mathrm{\ensuremath{\Vert}}}_{\mathrm{max}}$ did not exceed 0.5 for the most intense resonances. This value is in good agreement with realistic estimations for the resonant contribution ${\ensuremath{\chi}}^{(3)R}$ of the ${\mathrm{Pr}}^{3+}$ ions and ${\ensuremath{\chi}}^{(3)\mathrm{NR}}$ due to the host crystal.I report the observation of Raman resonances due to the $^{3}\mathrm{H}_{4}$${\ensuremath{\rightarrow}}^{3}$${\mathrm{F}}_{2}$ transition in ${\mathrm{Pr}}^{3+}$ ions by coherent anti-Stokes Raman scattering. The very weak resonances could only be measured in ${\mathrm{PrF}}_{3}$ under cryogenic conditions (2 K). The ratio C=\ensuremath{\Vert}${\ensuremath{\chi}}^{(3)R}$/${\ensuremath{\chi}}^{(3)\mathrm{NR}}$${\mathrm{\ensuremath{\Vert}}}_{\mathrm{max}}$ did not exceed 0.5 for the most intense resonances. This value is in good agreement with realistic estimations for the resonant contribution ${\ensuremath{\chi}}^{(3)R}$ of the ${\mathrm{Pr}}^{3+}$ ions and ${\ensuremath{\chi}}^{(3)\mathrm{NR}}$ due to the host crystal.

Physical review. B, Condensed matterMar 1, 19874 citations

The Spectra of the Doubly and Triply Ionized Rare Earths

G. H. Dieke, H. M. Crosswhite

Applied OpticsJul 1, 19631,115 citations

Experimental demonstration of multiphonon-assisted anti-Stokes and Stokes excitation of rare-earth ions (

{R}^{3+}

{\ensuremath{\alpha}}_{\mathrm{AS}}

and

{\ensuremath{\alpha}}_{\mathrm{S}}

for anti-Stokes and Stokes excitation are measured and linked to the Miyakawa-Dexter

\ensuremath{\alpha}

parameter for decay, leading to estimates for Pekar-Huang-Rhys coupling parameter

{S}_{0}

of about 0.04, in agreement with values obtained from one-phonon spectra or nonradiative-decay measurements. A semiempirical formula is deduced to obtain

\ensuremath{\alpha}

from only one parameter, an effective phonon energy.

I report the observation of Raman resonances due to the

^{3}\mathrm{H}_{4}

${\ensuremath{\rightarrow}}^{3}$

{\mathrm{F}}_{2}

transition in

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

ions by coherent anti-Stokes Raman scattering. The very weak resonances could only be measured in

{\mathrm{PrF}}_{3}

under cryogenic conditions (2 K). The ratio C=\ensuremath{\Vert}${\ensuremath{\chi}}^{(3)R}$/${\ensuremath{\chi}}^{(3)\mathrm{NR}}$${\mathrm{\ensuremath{\Vert}}}_{\mathrm{max}}$ did not exceed 0.5 for the most intense resonances. This value is in good agreement with realistic estimations for the resonant contribution ${\ensuremath{\chi}}^{(3)R}$ of the

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

ions and ${\ensuremath{\chi}}^{(3)\mathrm{NR}}$ due to the host crystal.