Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Annual Meeting Optical Society of America

Dynamics of monochromatic nonequilibrium phonons generated by defect-induced one-phonon absorption

W. A. Tolbert, William M. Dennis, William M. Yen

Published Jan 1, 1990• 0 citations
Publisher

Abstract

Defect-induced one-phonon absorption1 of far-infrared radiation is used to generate monochromatic nonequilibrium phonon populations in LaF3:Pr3+ at a range of frequencies throughout the acoustic band. The pump source for this generation mechanism is a transversely excited atmospheric-pressure CO2-laser-pumped superradiant cell. Phonon occupation numbers of order 10 are generated. Phonons are optically detected in a time-resolved frequency-selective manner by using the anti-Stokes absorption sideband of the 3P0 state of Pr3+. The lifetime of these phonons is determined and is found to obey the ω-5 dependence as predicted by the isotropic dispersionless model for anharmonic decay of acoustic phonons.2 The spectral dynamics associated with the decay of these phonons is also investigated and is compared with a rate-equation analysis that includes backfeeding of the decay products. The production of double-frequency phonons by a three-phonon confluence process is also demonstrated.

DOI
10.1364/oam.1990.fff1

Related papers

Dynamics of monochromatically generated nonequilibrium phonons in LaF3 : Pr3+

W. A. Tolbert, William M. Dennis, William M. Yen

The temporal evolution of nonequilibrium phonon populations in ${\mathrm{LaF}}_{3}$:${\mathrm{Pr}}^{3+}$ is investigated at low temperatures (1.8 K) utilizing pulsed, tunable, monochromatic generation and time-resolved, tunable, narrow-band detection. High occupation number, narrow-band phonon populations are generated via far-infrared pumping of defect-induced one-phonon absorption. Time-resolved, frequency-selective detection is provided by optical sideband absorption. Nonequilibrium phonon decay times are measured and attributed to anharmonic decay.

Physical Review Letters•Jul 30, 1990•31 citations

Spectral and temporal dynamics of nonequilibrium phonons in LaF3 : Pr3+

W. A. Tolbert, William M. Dennis, William M. Yen

Defect-induced one-phonon absorption is used to generate high-occupation-number narrow-band nonequilibrium phonon populations at a range of frequencies in ${\mathrm{LaF}}_{3}$:${\mathrm{Pr}}^{3+}$. The spectral and temporal dynamics associated with the return to equilibrium of these phonons is observed. Processes that dominate the spectral evolution are shown to be narrow-band phonon confluence, anharmonic decay, and the broadband confluence of anharmonic decay products. The experimental data are shown to be in good agreement with a phonon-occupation-number rate-equation analysis that incudes the above processes.

Physical review. B, Condensed matter•Aug 1, 1991•11 citations

Spectral and Temporal Dynamics of Nonequilibrium Phonons in YAG:Pr3+

Xiaojun Wang, William M. Dennis

We have investigated the spectral and temporal dynamics associated with phonon decay in the YAG:Pr3+ system at a range of temperature between 9 and 25 K. Nonequilibrium phonons were generated using defect induced one phonon absorption (DIOPA) of far infrared (FIR) radiation1. Phonon detection was achieved optically using a variation of absorption vibronic sideband phonon spectroscopy2.

Spectral Hole-Burning and Related Spectroscopies: Science and Applications•Jan 1, 1991•0 citations

Temperature effects in nonequilibrium phonon decay

Xiaojun Wang, William M. Dennis, William M. Yen

We have investigated the spectral and temporal dynamics associated with the interaction between monochromatic and thermal phonon distributions in YAG:${\mathrm{Pr}}^{3+}$. Using defect-induced one-phonon absorption to generate a monochromatic phonon distribution at 43.3 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$, we measure a ${\mathit{T}}^{\mathrm{\ensuremath{-}}3}$ dependence of the monochromatic phonon lifetime in the temperature range 9 to 25 K. We observe the evolution of additional broadband phonon distributions which do not occur at low temperatures.

Physical Review Letters•Nov 1, 1991•8 citations

Optical dephasing by nonequilibrium phonons in LaF3

Richard S. Meltzer, R. M. Macfarlane

Phonon-induced coherence loss (PICL) is produced by a monoenergetic nonequilibrium distribution of phonons in ${\mathrm{LaF}}_{3}$:${\mathrm{Pr}}^{3+}$. The phonons are generated by relaxation between excited states of the ${\mathrm{Pr}}^{3+}$ ion after selective excitation with a pulsed, tunable dye laser. The optical dephasing is observed from the effect on the free-induction decay of ${\mathrm{Pr}}^{3+}$ ions whose excited-state level separation is resonant with the phonons. It is shown that PICL is a sensitive detector of monoenergetic phonons, and can be used to study phonon dynamics. The observed rate of optical dephasing is reduced relative to an equivalent occupation of 23-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ phonons produced thermally.

Physical review. B, Condensed matter•Jul 15, 1985•17 citations

Dynamics of phonons in submicrometer zones generated by an optical waveguide

Robert Jan van Wijk, J. I. Dijkhuis, H. W. de Wijn

We introduce a technique utilizing the evanescent field of an optical waveguide to examine the dynamics of nonequilibrium high-frequency phonons resonant with optically excited centers in zones of submicrometer dimension. The technique is used to create a nearly saturated zone of excited ${\mathrm{Cr}}^{3+}$ ions at the surface of a 700-at. ppm ruby crystal at 1.5 K by optical pumping through the broad bands. At the same time, the optical pumping serves to generate resonant 29-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ phonons. The decay of the combined spin-phonon system, measured via the ${\mathit{R}}_{2}$ luminescence following interruption of the optical pumping, is explained by elastic spatial diffusion in parallel with spectral wipeout. The time constant for loss by spatial diffusion is derived rigorously from rate equations. Spectral wipeout is treated according to the model developed by Goossens et al. based on one-site inelastic scattering by weakly exchange-coupled ${\mathrm{Cr}}^{3+}$ pairs, but modified to include the appreciable elastic diffusion remaining after wipeout under the present extreme conditions. Spectral wipeout turns out to predominate at high excited-state concentration. The optical feeding into 2A\ifmmode\bar\else\textasciimacron\fi{}${(}^{2}$E) is found to result mainly from excited-state absorption starting from E\ifmmode\bar\else\textasciimacron\fi{}${(}^{2}$E), despite the low probability of the latter at the light wavelength used (514.5 nm).

Physical review. B, Condensed matter•Jun 1, 1991•0 citations
Defect-induced one-phonon absorption1 of far-infrared radiation is used to generate monochromatic nonequilibrium phonon populations in LaF3:Pr3+ at a range of frequencies throughout the acoustic band. The pump source for this generation mechanism is a transversely excited atmospheric-pressure CO2-laser-pumped superradiant cell. Phonon occupation numbers of order 10 are generated. Phonons are optically detected in a time-resolved frequency-selective manner by using the anti-Stokes absorption sideband of the 3P0 state of Pr3+. The lifetime of these phonons is determined and is found to obey the ω-5 dependence as predicted by the isotropic dispersionless model for anharmonic decay of acoustic phonons.2 The spectral dynamics associated with the decay of these phonons is also investigated and is compared with a rate-equation analysis that includes backfeeding of the decay products. The production of double-frequency phonons by a three-phonon confluence process is also demonstrated.
The temporal evolution of nonequilibrium phonon populations in LaF3{\mathrm{LaF}}_{3}LaF3​:Pr3+{\mathrm{Pr}}^{3+}Pr3+ is investigated at low temperatures (1.8 K) utilizing pulsed, tunable, monochromatic generation and time-resolved, tunable, narrow-band detection. High occupation number, narrow-band phonon populations are generated via far-infrared pumping of defect-induced one-phonon absorption. Time-resolved, frequency-selective detection is provided by optical sideband absorption. Nonequilibrium phonon decay times are measured and attributed to anharmonic decay.
Defect-induced one-phonon absorption is used to generate high-occupation-number narrow-band nonequilibrium phonon populations at a range of frequencies in LaF3{\mathrm{LaF}}_{3}LaF3​:Pr3+{\mathrm{Pr}}^{3+}Pr3+. The spectral and temporal dynamics associated with the return to equilibrium of these phonons is observed. Processes that dominate the spectral evolution are shown to be narrow-band phonon confluence, anharmonic decay, and the broadband confluence of anharmonic decay products. The experimental data are shown to be in good agreement with a phonon-occupation-number rate-equation analysis that incudes the above processes.
We have investigated the spectral and temporal dynamics associated with the interaction between monochromatic and thermal phonon distributions in YAG:Pr3+{\mathrm{Pr}}^{3+}Pr3+. Using defect-induced one-phonon absorption to generate a monochromatic phonon distribution at 43.3 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$, we measure a ${\mathit{T}}^{\mathrm{\ensuremath{-}}3}$ dependence of the monochromatic phonon lifetime in the temperature range 9 to 25 K. We observe the evolution of additional broadband phonon distributions which do not occur at low temperatures.
Phonon-induced coherence loss (PICL) is produced by a monoenergetic nonequilibrium distribution of phonons in LaF3{\mathrm{LaF}}_{3}LaF3​:Pr3+{\mathrm{Pr}}^{3+}Pr3+. The phonons are generated by relaxation between excited states of the Pr3+{\mathrm{Pr}}^{3+}Pr3+ ion after selective excitation with a pulsed, tunable dye laser. The optical dephasing is observed from the effect on the free-induction decay of Pr3+{\mathrm{Pr}}^{3+}Pr3+ ions whose excited-state level separation is resonant with the phonons. It is shown that PICL is a sensitive detector of monoenergetic phonons, and can be used to study phonon dynamics. The observed rate of optical dephasing is reduced relative to an equivalent occupation of 23-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ phonons produced thermally.
We introduce a technique utilizing the evanescent field of an optical waveguide to examine the dynamics of nonequilibrium high-frequency phonons resonant with optically excited centers in zones of submicrometer dimension. The technique is used to create a nearly saturated zone of excited Cr3+{\mathrm{Cr}}^{3+}Cr3+ ions at the surface of a 700-at. ppm ruby crystal at 1.5 K by optical pumping through the broad bands. At the same time, the optical pumping serves to generate resonant 29-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ phonons. The decay of the combined spin-phonon system, measured via the R2{\mathit{R}}_{2}R2​ luminescence following interruption of the optical pumping, is explained by elastic spatial diffusion in parallel with spectral wipeout. The time constant for loss by spatial diffusion is derived rigorously from rate equations. Spectral wipeout is treated according to the model developed by Goossens et al. based on one-site inelastic scattering by weakly exchange-coupled Cr3+{\mathrm{Cr}}^{3+}Cr3+ pairs, but modified to include the appreciable elastic diffusion remaining after wipeout under the present extreme conditions. Spectral wipeout turns out to predominate at high excited-state concentration. The optical feeding into 2A\ifmmode\bar\else\textasciimacron\fi{}(2{(}^{2}(2E) is found to result mainly from excited-state absorption starting from E\ifmmode\bar\else\textasciimacron\fi{}(2{(}^{2}(2E), despite the low probability of the latter at the light wavelength used (514.5 nm).