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

Journal of Applied Physics

Phonon-Terminated Coherent Emission from V2+ Ions in MgF2

L. F. Johnson, Howard J. Guggenheim

Published Nov 1, 1967• 58 citations
Publisher

Abstract

Infrared fluorescence and phonon-terminated stimulated emission from V2+ ions in MgF2 is reported. Fluorescence is produced in transitions from the first excited state 4T2(4F) to the ground state 4A2(4F). Stimulated emission occurs in the vibronic sideband at 1.1217 μ (8915 cm−1) and lies 1166 cm−1 from the no-phonon line. A gain curve calculated from the optical spectra predicts an oscillation frequency in reasonable agreement with the observed frequency, with a cross section for stimulated emission of 8×10−21 cm2. From the effect of excited state absorption on the gain profile it is concluded that the excited state absorption cross section at the maser frequency is <3×10−21 cm2.

DOI
10.1063/1.1709230

Related papers

Optical Maser Emission from Trivalent Praseodymium in Calcium Tungstate

Avigail Yariv, Sergio P. S. Porto, KURT NASSAU

Coherent emission at 1.047 μ from trivalent praseodymium in calcium tungstate was observed. This emission coincides with strong infrared fluorescence at the same wavelength and was found to be stimulated mostly by absorption of blue light by the 3P0, 3P1, and 3P2 bands. The emission corresponds to a 1G4→3H4 transition with the terminal level 377 cm−1 from the ground state. The oscillation threshold was the same at 4.2°, 20°, and 78°K. No stimulated emission was observed at room temperature. The lifetime of the metastable state 1G4 is 50×10−3 sec. A new technique used to measure the lifetime is described.

Journal of Applied Physics•Aug 1, 1962•52 citations

Stimulated Raman emission of coherent phonons by impurities in a crystal

Benjamin Fain

The possibility of stimulated emission of coherent phonons by impurities (ions) embedded in a crystal is considered. It is shown that when the ions with homogeneously broadened levels are subjected to an electromagnetic field, the frequency Ω of which is larger than an eigenfrequency of the ion ω21, at the Raman frequency ωq=Ω−ω21, a coherent stimulated emission of phonons may emerge. The absorption rate of the pumping electromagnetic field has a singularity near the threshold of the phonon self-excitation.

Journal of Applied Physics•Sep 1, 1983•6 citations

Stimulated and Fluorescent Optical Emission in Ruby From 4, 2 to 300°K : Zero-field Splitting and Mode Structure

I. J. D’Haenens, Charles K. Asawa

The spectral character of the stimulated emission from ruby has been investigated; we found that the zero-field splitting (0.38 cm−1) of the 4A2 ground level and the cavity optical length and its reflectivity determine the spectral character of this emission. At 300°K the system is induced into oscillation in a number of cavity modes separated by Δv = (2le12)−1, where l is the length of the resonator and e12 is the index of refraction for the ordinary ray. At T≅80°K the Ē(2E) → ±32(A2) and the Ē(2E) → ±12(4A2) transitions were identified in the stimulated emission spectrum. Each can oscillate in an axial cavity mode (or modes) plus an off-axis mode at the center of the transition. At 4.2°K the system oscillates in off-axis modes, unless the length of the cavity l is such that it has axial resonances coincident with the transition frequencies. An analysis of the temperature dependence of the oscillation threshold for the separate transitions is presented and is compared with the observed behavior.

Quantum Electronics•Jan 1, 1964•0 citations

Spectroscopy and Optical Maser Action in Sr F2 : Sm2+

P. P. Sorokin, M. J. Stevenson, J. R. Lankard +1 more

A crystal of Sr${\mathrm{F}}_{2}$: ${\mathrm{Sm}}^{2+}$ was operated as a pulsed optical maser at temperatures close to 4.2\ifmmode^\circ\else\textdegree\fi{}K. The 6969 \AA{} output corresponds to the wavelength of an exceedingly sharp line ($\ensuremath{\Delta}\ensuremath{\nu}<0.6$ ${\mathrm{cm}}^{\ensuremath{-}1}$) in which almost all of the low-temperature fluorescence is concentrated. In contrast to what prevails in Ca${\mathrm{F}}_{2}$: ${\mathrm{Sm}}^{+2}$ masers, the output is characterized by strong relaxation oscillations. This may be explained by the large difference in the fluorescent lifetimes in the two systems. While in Ca${\mathrm{F}}_{2}$: ${\mathrm{Sm}}^{2+}$ the value of $\ensuremath{\tau}$ is approximately 1.5\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}6}$ sec, in Sr${\mathrm{F}}_{2}$: ${\mathrm{Sm}}^{2+}$ it has a value of 15 msec. The reason for the large difference in $\ensuremath{\tau}$ values, in turn, depends upon the relative proximity of the long-wavelength edge of the red band to the position of the metastable $^{5}D_{0}$ level from which fluorescence occurs. Absorption measurements taken at helium temperatures on Sr${\mathrm{F}}_{2}$: ${\mathrm{Sm}}^{2+}$ show that the lowest vibrational level of the lowest lying $4f\ensuremath{-}5d$ band lies \ensuremath{\sim}600 ${\mathrm{cm}}^{\ensuremath{-}1}$ above the position of the $^{5}D_{0}$ level while in Ca${\mathrm{F}}_{2}$: ${\mathrm{Sm}}^{2+}$ there is near coincidence of the corresponding levels and consequently strong configurational mixing. Crystals of Sr${\mathrm{Cl}}_{2}$: ${\mathrm{Sm}}^{2+}$ were also studied in this regard and display an expected close similarity in spectral characteristics to Sr${\mathrm{F}}_{2}$: ${\mathrm{Sm}}^{2+}$. The vibrational structure on the $4f\ensuremath{-}5d$ bands is much more pronounced, however, than in Ca${\mathrm{F}}_{2}$: ${\mathrm{Sm}}^{2+}$ and Sr${\mathrm{F}}_{2}$: ${\mathrm{Sm}}^{2+}$, indicating weaker coupling to the lattice in the excited $5d$ state. A tentative interpretation for the splitting of the red band seen in the absorption spectra of ${\mathrm{Sm}}^{2+}$ ions is given.

Physical Review•Jul 15, 1962•66 citations

Stimulated emission of Co^2+ ions in transparent glass-ceramics

Yu.V. Volk, Alexander M. Malyarevich, Konstantin V. Yumashev +4 more

This paper investigates the differential absorption spectra of a number of transparent spinel-based cobalt-containing aluminosilicate glass-ceramics in the 550-700-nm range. A stimulated emission band accompanying transitions between the 4T1(4P) and 4A2 levels of the tetracoordinated Co2+ ion is detected in all the materials. Depending on the composition of the glass-ceramic, the effective stimulated-emission cross sections of the Co2+ ions at the maximum of this band are estimated at (4-5)×10−19 cm2.

Journal of Optical Technology•Sep 1, 2006•0 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
Infrared fluorescence and phonon-terminated stimulated emission from V2+ ions in MgF2 is reported. Fluorescence is produced in transitions from the first excited state 4T2(4F) to the ground state 4A2(4F). Stimulated emission occurs in the vibronic sideband at 1.1217 μ (8915 cm−1) and lies 1166 cm−1 from the no-phonon line. A gain curve calculated from the optical spectra predicts an oscillation frequency in reasonable agreement with the observed frequency, with a cross section for stimulated emission of 8×10−21 cm2. From the effect of excited state absorption on the gain profile it is concluded that the excited state absorption cross section at the maser frequency is <3×10−21 cm2.
Coherent emission at 1.047 μ from trivalent praseodymium in calcium tungstate was observed. This emission coincides with strong infrared fluorescence at the same wavelength and was found to be stimulated mostly by absorption of blue light by the 3P0, 3P1, and 3P2 bands. The emission corresponds to a 1G4→3H4 transition with the terminal level 377 cm−1 from the ground state. The oscillation threshold was the same at 4.2°, 20°, and 78°K. No stimulated emission was observed at room temperature. The lifetime of the metastable state 1G4 is 50×10−3 sec. A new technique used to measure the lifetime is described.
The possibility of stimulated emission of coherent phonons by impurities (ions) embedded in a crystal is considered. It is shown that when the ions with homogeneously broadened levels are subjected to an electromagnetic field, the frequency Ω of which is larger than an eigenfrequency of the ion ω21, at the Raman frequency ωq=Ω−ω21, a coherent stimulated emission of phonons may emerge. The absorption rate of the pumping electromagnetic field has a singularity near the threshold of the phonon self-excitation.
The spectral character of the stimulated emission from ruby has been investigated; we found that the zero-field splitting (0.38 cm−1) of the 4A2 ground level and the cavity optical length and its reflectivity determine the spectral character of this emission. At 300°K the system is induced into oscillation in a number of cavity modes separated by Δv = (2le12)−1, where l is the length of the resonator and e12 is the index of refraction for the ordinary ray. At T≅80°K the Ē(2E) → ±32(A2) and the Ē(2E) → ±12(4A2) transitions were identified in the stimulated emission spectrum. Each can oscillate in an axial cavity mode (or modes) plus an off-axis mode at the center of the transition. At 4.2°K the system oscillates in off-axis modes, unless the length of the cavity l is such that it has axial resonances coincident with the transition frequencies. An analysis of the temperature dependence of the oscillation threshold for the separate transitions is presented and is compared with the observed behavior.
A crystal of SrF2{\mathrm{F}}_{2}F2​: Sm2+{\mathrm{Sm}}^{2+}Sm2+ was operated as a pulsed optical maser at temperatures close to 4.2\ifmmode^\circ\else\textdegree\fi{}K. The 6969 \AA{} output corresponds to the wavelength of an exceedingly sharp line ($\ensuremath{\Delta}\ensuremath{\nu}<0.6$ ${\mathrm{cm}}^{\ensuremath{-}1}$) in which almost all of the low-temperature fluorescence is concentrated. In contrast to what prevails in CaF2{\mathrm{F}}_{2}F2​: Sm+2{\mathrm{Sm}}^{+2}Sm+2 masers, the output is characterized by strong relaxation oscillations. This may be explained by the large difference in the fluorescent lifetimes in the two systems. While in CaF2{\mathrm{F}}_{2}F2​: Sm2+{\mathrm{Sm}}^{2+}Sm2+ the value of $\ensuremath{\tau}$ is approximately 1.5\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}6}$ sec, in SrF2{\mathrm{F}}_{2}F2​: Sm2+{\mathrm{Sm}}^{2+}Sm2+ it has a value of 15 msec. The reason for the large difference in $\ensuremath{\tau}$ values, in turn, depends upon the relative proximity of the long-wavelength edge of the red band to the position of the metastable 5D0^{5}D_{0}5D0​ level from which fluorescence occurs. Absorption measurements taken at helium temperatures on SrF2{\mathrm{F}}_{2}F2​: Sm2+{\mathrm{Sm}}^{2+}Sm2+ show that the lowest vibrational level of the lowest lying $4f\ensuremath{-}5d$ band lies \ensuremath{\sim}600 ${\mathrm{cm}}^{\ensuremath{-}1}$ above the position of the 5D0^{5}D_{0}5D0​ level while in CaF2{\mathrm{F}}_{2}F2​: Sm2+{\mathrm{Sm}}^{2+}Sm2+ there is near coincidence of the corresponding levels and consequently strong configurational mixing. Crystals of SrCl2{\mathrm{Cl}}_{2}Cl2​: Sm2+{\mathrm{Sm}}^{2+}Sm2+ were also studied in this regard and display an expected close similarity in spectral characteristics to SrF2{\mathrm{F}}_{2}F2​: Sm2+{\mathrm{Sm}}^{2+}Sm2+. The vibrational structure on the $4f\ensuremath{-}5d$ bands is much more pronounced, however, than in CaF2{\mathrm{F}}_{2}F2​: Sm2+{\mathrm{Sm}}^{2+}Sm2+ and SrF2{\mathrm{F}}_{2}F2​: Sm2+{\mathrm{Sm}}^{2+}Sm2+, indicating weaker coupling to the lattice in the excited 5d5d5d state. A tentative interpretation for the splitting of the red band seen in the absorption spectra of Sm2+{\mathrm{Sm}}^{2+}Sm2+ ions is given.
This paper investigates the differential absorption spectra of a number of transparent spinel-based cobalt-containing aluminosilicate glass-ceramics in the 550-700-nm range. A stimulated emission band accompanying transitions between the 4T1(4P) and 4A2 levels of the tetracoordinated Co2+ ion is detected in all the materials. Depending on the composition of the glass-ceramic, the effective stimulated-emission cross sections of the Co2+ ions at the maximum of this band are estimated at (4-5)×10−19 cm2.