Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Self-induced coherence and conductivity of glow discharge

L. Petrov, Dimitar G. Slavov, Vladimir R. Arsov, А. П. Горбенко, Vasilka Steflekova, Vladimir A. Polischuk, Dimo Zhechev, G. Todorov

Published Mar 2, 2007• 0 citations

Publisher

Abstract

Comparative studies of MO resonances and MG responses with and without resonant laser irradiation were carried out to establish the interconnection of the effects and the influence of the self-alignment destruction on the MO signal in positive column discharge. These studies aim to clarify the possible formation mechanisms of the neon 1 si (2p53s) states coherences and to examine the possibility to use the galvanic resonances for estimation of the relaxation constants of the neon 1 s5 state.

DOI: 10.1117/12.726890

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Peculiarities of the magneto-optical resonances on 2p53s states in a NE glow discharge

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In continuation of our previous works, systematic investigation of the magneto-optical (MO) resonances from the 3P1(1s4) (Pashen notation), 3P2 (1s5), and 3P0 (1s3) levels of NeI was carried out. This study aims to clarify the formation mechanisms of the neon 1si (2p53s) states coherences. Anomalous MO resonances are experimentally observed and the possible mechanisms of their creation are discussed.

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Cascade effects in neon life time measurements

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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Self-induced coherence and conductivity of glow discharge

L. Petrov, Dimitar G. Slavov, Vladimir R. Arsov, А. П. Горбенко, Vasilka Steflekova, Vladimir A. Polischuk, Dimo Zhechev, G. Todorov

Published Mar 2, 2007• 0 citations

Publisher

Abstract

DOI: 10.1117/12.726890

Related papers

Влияние интерференции атомных состояний на гальванические свойства плазмы газового разряда

А. П. Горбенко, A. Ya. Polishchuk, Г. Ц. Тодоров +1 more

Comparative studies of magneto-optical (MO) resonances and magneto-galvanic (MG) responses with and without resonant laser irradiation are earned out to establish the interconnection of the effects and the influence of the selfalignment destruction on the MO signal in positive column discharge. These studies aim to clarify the possible formation mechanisms of the neon Is, (2p 53s) states coherences and to examine the possibility to use the galvanic resonances for estimation of the relaxation constants of the neon lr state.Comparative studies of magneto-optical (MO) resonances and magneto-galvanic (MG) responses with and without resonant laser irradiation are earned out to establish the interconnection of the effects and the influence of the selfalignment destruction on the MO signal in positive column discharge. These studies aim to clarify the possible formation mechanisms of the neon Is, (2p 53s) states coherences and to examine the possibility to use the galvanic resonances for estimation of the relaxation constants of the neon lr state.

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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIEJun 15, 20070 citations

Galvanic manifestation of coherent degenerate Zeeman sublevels in a gas discharge

Vasilka Steflekova, Dimo Zhechev

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Disalignment of excited atoms by radiation re-absorption: neon 2p2atoms in a discharge plasma

Manabu Seo, Masanori Nimura, Masahiro Hasuo +1 more

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Cascade effects in neon life time measurements

C. Gerald Carrington

Alignment cascade phenomena have been studied in the neon 2p levels (Paschen notation) Hanle effect and double resonance techniques in a mild discharge. The levels are aligned directly by an optical excitation mechanism. Most 2p levels show evidence of alignment cascade from the 2s 4 , 3s 1 or 3d levels below 0.1 Torr; addition of argon impurities greatly enhances the cascade signal relative to the direct alignment signal. Data used previously in pressure broadening studies are shown to be free of cascade errors and are used to establish upper limits for the 2p level life times. A correction for coherence narrowing is estimated; this gives natural life times systematically less than those obtained by methods in which cascade effects are not carefully eliminated. In common with other Hanle effect measurements for these levels the values are marginally smaller than the threshold life times of Bennett and Kindlmann (1966).Alignment cascade phenomena have been studied in the neon 2p levels (Paschen notation) Hanle effect and double resonance techniques in a mild discharge. The levels are aligned directly by an optical excitation mechanism. Most 2p levels show evidence of alignment cascade from the 2s 4 , 3s 1 or 3d levels below 0.1 Torr; addition of argon impurities greatly enhances the cascade signal relative to the direct alignment signal. Data used previously in pressure broadening studies are shown to be free of cascade errors and are used to establish upper limits for the 2p level life times. A correction for coherence narrowing is estimated; this gives natural life times systematically less than those obtained by methods in which cascade effects are not carefully eliminated. In common with other Hanle effect measurements for these levels the values are marginally smaller than the threshold life times of Bennett and Kindlmann (1966).

Journal of Physics B Atomic and Molecular PhysicsAug 1, 197214 citations

Collision-Induced Transitions within Excited Levels of Neon

Joel H. Parks, Ali Javan

The interaction of an intense optical-maser field with excited atoms in a gas discharge leads to a considerable change in the population of those levels which are resonant at the maser frequency. This will cause a change in the population of other levels that are connected to the maser levels through collision-induced nonradiative as well as radiative transitions. Using the 1.15-\ensuremath{\mu} optical maser, these effects have been studied in detail for the $2s$ levels of neon where the changes are completely due to collisions. By analyzing the intensity changes in spontaneous emission originating from a gas-discharge cell placed within the maser resonator, we have observed the approach to a partial thermalization of two closely spaced levels. In this way we have been able to obtain the atomic-collision cross section for excitation transfer between the $2{s}_{2}$ and $2{s}_{3}$ levels. In pure neon this has been found to be ${\ensuremath{\sigma}}_{23}=(2.3\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}16}$ ${\mathrm{cm}}^{2}$ . For a helium-neon mixture the measured cross section is ${\ensuremath{\sigma}}_{23}=(1.8\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}16}$ ${\mathrm{cm}}^{2}$ . The experimental method used to determine these cross sections eliminates the uncertainties caused by the effects of electron-atom collisions and radiative cascade. These techniques also yield the ratio of the Einstein coefficients for the transitions $2{s}_{2}\ensuremath{\rightarrow}2{p}_{10}$ and $2{s}_{3}\ensuremath{\rightarrow}2{p}_{10}$. The measured ratio is $\frac{{A}_{2}}{{A}_{3}}=3.0\ifmmode\pm\else\textpm\fi{}0.4$.The interaction of an intense optical-maser field with excited atoms in a gas discharge leads to a considerable change in the population of those levels which are resonant at the maser frequency. This will cause a change in the population of other levels that are connected to the maser levels through collision-induced nonradiative as well as radiative transitions. Using the 1.15-\ensuremath{\mu} optical maser, these effects have been studied in detail for the $2s$ levels of neon where the changes are completely due to collisions. By analyzing the intensity changes in spontaneous emission originating from a gas-discharge cell placed within the maser resonator, we have observed the approach to a partial thermalization of two closely spaced levels. In this way we have been able to obtain the atomic-collision cross section for excitation transfer between the $2{s}_{2}$ and $2{s}_{3}$ levels. In pure neon this has been found to be ${\ensuremath{\sigma}}_{23}=(2.3\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}16}$ ${\mathrm{cm}}^{2}$. For a helium-neon mixture the measured cross section is ${\ensuremath{\sigma}}_{23}=(1.8\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}16}$ ${\mathrm{cm}}^{2}$. The experimental method used to determine these cross sections eliminates the uncertainties caused by the effects of electron-atom collisions and radiative cascade. These techniques also yield the ratio of the Einstein coefficients for the transitions $2{s}_{2}\ensuremath{\rightarrow}2{p}_{10}$ and $2{s}_{3}\ensuremath{\rightarrow}2{p}_{10}$. The measured ratio is $\frac{{A}_{2}}{{A}_{3}}=3.0\ifmmode\pm\else\textpm\fi{}0.4$.

Physical ReviewAug 30, 196544 citations

2s

levels of neon where the changes are completely due to collisions. By analyzing the intensity changes in spontaneous emission originating from a gas-discharge cell placed within the maser resonator, we have observed the approach to a partial thermalization of two closely spaced levels. In this way we have been able to obtain the atomic-collision cross section for excitation transfer between the

2{s}_{2}

and

2{s}_{3}

levels. In pure neon this has been found to be ${\ensuremath{\sigma}}_{23}=(2.3\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}16}$

{\mathrm{cm}}^{2}

. For a helium-neon mixture the measured cross section is ${\ensuremath{\sigma}}_{23}=(1.8\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}16}$

{\mathrm{cm}}^{2}

. The experimental method used to determine these cross sections eliminates the uncertainties caused by the effects of electron-atom collisions and radiative cascade. These techniques also yield the ratio of the Einstein coefficients for the transitions $2{s}_{2}\ensuremath{\rightarrow}2{p}_{10}$ and $2{s}_{3}\ensuremath{\rightarrow}2{p}_{10}$. The measured ratio is $\frac{{A}_{2}}{{A}_{3}}=3.0\ifmmode\pm\else\textpm\fi{}0.4$.