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

Physical review. B, Condensed matter

Stimulated emission of 0.2-THz phonons in La F3 : Er3+

D. J. Sox, John E. Rives, Richard S. Meltzer

Published Apr 15, 1982• 18 citations
Publisher

Abstract

Stimulated emission of phonons in the 0.2-THz frequency range is observed in La${\mathrm{F}}_{3}$:${\mathrm{Er}}^{3+}$. The phonons are generated in the relaxation between the Kramers components of the $^{4}S_{\frac{3}{2}}(1)$ state of ${\mathrm{Er}}^{3+}$ split in a magnetic field after inverting the population with a pulsed tunable dye laser. The stimulated emission is identified from the temporal behavior of the luminescence from the upper Kramers component which shows a speedup in the relaxation during inversion. The population dynamics are analyzed with the rate equations for the system. Comparison with experiment indicates strong preferential stimulated emission along the axis of the cylindrically excited volume and a gain of up to 5 ${\mathrm{mm}}^{\ensuremath{-}1}$. The population inversion exists sufficiently long for phonon propagation over macroscopic distances and the phonon frequency is tunable with the magnetic field.

DOI
10.1103/physrevb.25.5064

Related papers

STIMULATED EMISSION OF TUNABLE HIGH FREQUENCY PHONONS IN LaF3 : Er3+

D. J. Sox, John E. Rives, Richard S. Meltzer

We describe a case of stimulated emission of high frequency phonons (~ 0.2 THz) using optical excitation to invert the population of a pair of Kramer's states split in a magnetic field. The phonons are tunable with a magnetic field and the population inversion exists sufficiently long for phonon propagation over macroscopic sample dimensions. Analysis using rate equations suggests preferential emission along the axis of the optically excited volume.

Le Journal de Physique Colloques•Dec 1, 1981•1 citation

Stimulated emission of phonons in an acoustical cavity

Peter A. Fokker, J. I. Dijkhuis, H. W. de Wijn

Stimulated emission is studied of phonons resonant with the metastable Zeeman-split E-bar${(}^{2}$E) doublet in ruby. Initial population inversion of this two-level system is prepared by selective pulsed optical pumping, and the ensuing stimulated emission of resonant phonons is observed via an accelerated growth of the luminescence intensity emanating from the lower level. Under favorable conditions, a periodic recurrence of the process of stimulated emission is observed, which points to a phonon cavity formed by the end faces of the crystal in combination with a limited interaction length of the resonant phonons. To analyze these phenomena in detail, use is made of rate equations for the phonon occupation and the level populations with explicit account of their position dependences. With plausible assumptions an analytic solution of these equations is achieved, which excellently fits the data. The effect of lattice anharmonicity is shown to depend on the phonon energy in agreement with the theoretical prediction.

Physical review. B, Condensed matter•Feb 1, 1997•45 citations

Optically excited ruby as a saser: Experiment and theory

Lieuwe Gijsbert Tilstra, A. F. M. Arts, H. W. de Wijn

Avalanches of phonons are generated following population inversion of the Zeeman-split $\overline{E}(^{2}E)$ Kramers doublet in a single crystal of dilute ruby $({\mathrm{Al}}_{2}{\mathrm{O}}_{3}:{\mathrm{Cr}}^{3+})$ at $1.4\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. The inversion is achieved in a narrow zone of limited extent by selective pulsed optical pumping, and the phonons are detected via luminescence. The associated acoustic wave emanating from the zone propagates through the crystal, reverberates in the acoustic cavity formed by the crystalline end faces, and engages in further amplification each time it passes through the zone until the inversion becomes exhausted. The systems thus acts as a saser (sound amplification by stimulated emission of radiation). The avalanche is adequately described by coherent Bloch equations governing the acoustic wave and the interacting spin polarization, the losses being due to surface scattering and divergence. This conclusion holds good upon reducing the resonance length of the zone by a gradient magnetic field. Finally, the frequency and angular distributions of the avalanche are measured by using two disjunct zones located at opposite ends of the crystal, one serving as generator and the other as detector, in conjunction with a gradient field and lateral displacement. The frequency spread is found to be compatible with the inhomogeneously broadened transition within $\overline{E}(^{2}E)$, while the angular divergence is determined by the geometry of the zone.

Physical Review B•Jul 9, 2007•19 citations

Mechanism of a population inversion between the4I11/2and4I13/2levels of the Er3+ion in Y3AI5O12crystals

V I Zhekov, Boris V. Zubov, Vladimir A. Lobachev +3 more

Studies of the spectra of stimulated emission from Y 3 AI 5 O 12 :Er 3+ crystals ( 4 I 11/2 – 4 I 13/2 ) containing 20 wt. % activator ions, showed that, as the temperature decreased from 300 to 77°K, a change was observed in the emission wavelength (at T = 300°K it was found that λ 1 = 2.9364 μ λ 2 = 2.8310 μ and at T = 77°K it was found that λ 1 = 2.6930 μ , λ 2 = 2.8970 μ ). This could not be attributed to a thermal redistribution of the populations of the Stark components of the 4 I 11/2 and 4 I 13/2 upper and lower active levels. An analysis of the results showed that the temperature shift of the stimulated emission spectrum was due to changes in the processes of relaxation of excitation from the upper levels of the Er 3+ ion which caused substantial changes in the populations of the 4 I 11/2 and 4 I 13/2 multiplets.

Soviet Journal of Quantum Electronics•Apr 30, 1980•20 citations

Far-infrared stimulated emission from optically excited bismuth donors in silicon

Sergei G. Pavlov, Heinz‐Wilhelm Hübers, Mark Hermann Rümmeli +4 more

Far-infrared stimulated emission from optically pumped neutral Bi donors in silicon has been obtained. Lasing with wavelengths of 52.2 and 48.6 μm from the intra-center 2p±→1s(E:Γ8),1s(T2:Γ8) transitions has been realized under CO2 laser pumping. The population inversion mechanism is based on fast optical-phonon-assisted relaxation from the 2p0 and 2s excited states directly to the ground 1s(A) state leading to relatively small population in the intermediate 1s(E), 1s(T2) excited states.

Applied Physics Letters•Jun 24, 2002•58 citations

SASER action in optically excited ruby: Angular and spectral distribution

Lieuwe Gijsbert Tilstra, A. F. M. Arts, H. W. de Wijn

Selective pulsed optical excitation is used in 500-at.ppm ruby (Al 2 O 3 :Cr 3+ ) at 1.4 K to prepare complete population inversion of the Zeeman-split Ē( 2 E ) doublet in a zone of limited size. The inversion results in prolific stimulated emission of phonons resonant with the one-phonon transition connecting the doublet states. The phonons are detected via the R 1 luminescence. The angular and spectral distributions of the associated acoustic wave are measured using a geometry with inverted zones at either end of the crystal, one serving as generator and the other as detector. The divergence appears to be governed by the geometry of the zone, while the spectral distribution is, within errors, in keeping with the inhomogeneously broadened phonon transition.

Journal of Physics Conference Series•Dec 1, 2007•1 citation
Stimulated emission of phonons in the 0.2-THz frequency range is observed in LaF3{\mathrm{F}}_{3}F3​:Er3+{\mathrm{Er}}^{3+}Er3+. The phonons are generated in the relaxation between the Kramers components of the 4S32(1)^{4}S_{\frac{3}{2}}(1)4S23​​(1) state of Er3+{\mathrm{Er}}^{3+}Er3+ split in a magnetic field after inverting the population with a pulsed tunable dye laser. The stimulated emission is identified from the temporal behavior of the luminescence from the upper Kramers component which shows a speedup in the relaxation during inversion. The population dynamics are analyzed with the rate equations for the system. Comparison with experiment indicates strong preferential stimulated emission along the axis of the cylindrically excited volume and a gain of up to 5 mm\ensuremath−1{\mathrm{mm}}^{\ensuremath{-}1}mm\ensuremath−1. The population inversion exists sufficiently long for phonon propagation over macroscopic distances and the phonon frequency is tunable with the magnetic field.
Stimulated emission is studied of phonons resonant with the metastable Zeeman-split E-bar(2{(}^{2}(2E) doublet in ruby. Initial population inversion of this two-level system is prepared by selective pulsed optical pumping, and the ensuing stimulated emission of resonant phonons is observed via an accelerated growth of the luminescence intensity emanating from the lower level. Under favorable conditions, a periodic recurrence of the process of stimulated emission is observed, which points to a phonon cavity formed by the end faces of the crystal in combination with a limited interaction length of the resonant phonons. To analyze these phenomena in detail, use is made of rate equations for the phonon occupation and the level populations with explicit account of their position dependences. With plausible assumptions an analytic solution of these equations is achieved, which excellently fits the data. The effect of lattice anharmonicity is shown to depend on the phonon energy in agreement with the theoretical prediction.
Avalanches of phonons are generated following population inversion of the Zeeman-split E‾(2E)\overline{E}(^{2}E)E(2E) Kramers doublet in a single crystal of dilute ruby (Al2O3:Cr3+)({\mathrm{Al}}_{2}{\mathrm{O}}_{3}:{\mathrm{Cr}}^{3+})(Al2​O3​:Cr3+) at 1.4K1.4\phantom{\rule{0.3em}{0ex}}\mathrm{K}1.4K. The inversion is achieved in a narrow zone of limited extent by selective pulsed optical pumping, and the phonons are detected via luminescence. The associated acoustic wave emanating from the zone propagates through the crystal, reverberates in the acoustic cavity formed by the crystalline end faces, and engages in further amplification each time it passes through the zone until the inversion becomes exhausted. The systems thus acts as a saser (sound amplification by stimulated emission of radiation). The avalanche is adequately described by coherent Bloch equations governing the acoustic wave and the interacting spin polarization, the losses being due to surface scattering and divergence. This conclusion holds good upon reducing the resonance length of the zone by a gradient magnetic field. Finally, the frequency and angular distributions of the avalanche are measured by using two disjunct zones located at opposite ends of the crystal, one serving as generator and the other as detector, in conjunction with a gradient field and lateral displacement. The frequency spread is found to be compatible with the inhomogeneously broadened transition within E‾(2E)\overline{E}(^{2}E)E(2E), while the angular divergence is determined by the geometry of the zone.
Studies of the spectra of stimulated emission from Y 3 AI 5 O 12 :Er 3+ crystals ( 4 I 11/2 – 4 I 13/2 ) containing 20 wt. % activator ions, showed that, as the temperature decreased from 300 to 77°K, a change was observed in the emission wavelength (at T = 300°K it was found that λ 1 = 2.9364 μ λ 2 = 2.8310 μ and at T = 77°K it was found that λ 1 = 2.6930 μ , λ 2 = 2.8970 μ ). This could not be attributed to a thermal redistribution of the populations of the Stark components of the 4 I 11/2 and 4 I 13/2 upper and lower active levels. An analysis of the results showed that the temperature shift of the stimulated emission spectrum was due to changes in the processes of relaxation of excitation from the upper levels of the Er 3+ ion which caused substantial changes in the populations of the 4 I 11/2 and 4 I 13/2 multiplets.
Selective pulsed optical excitation is used in 500-at.ppm ruby (Al 2 O 3 :Cr 3+ ) at 1.4 K to prepare complete population inversion of the Zeeman-split Ē( 2 E ) doublet in a zone of limited size. The inversion results in prolific stimulated emission of phonons resonant with the one-phonon transition connecting the doublet states. The phonons are detected via the R 1 luminescence. The angular and spectral distributions of the associated acoustic wave are measured using a geometry with inverted zones at either end of the crystal, one serving as generator and the other as detector. The divergence appears to be governed by the geometry of the zone, while the spectral distribution is, within errors, in keeping with the inhomogeneously broadened phonon transition.