Physical Review Letters

Excess dephasing in photon-echo experiments arising from excitation-induced electronic level shifts

Huang Jin, J.M. Zhang, A. Lezama, THOMAS W. MOSSBERG

Published Jul 3, 1989• 101 citations

Abstract

Working on the $^{7}\mathrm{F}_{0}$${\mathrm{\ensuremath{-}}}^{5}$${\mathrm{D}}_{0}$ transition of ${\mathrm{Eu}}^{3+}$ in ${\mathrm{Y}}_{2}$${\mathrm{O}}_{3}$, we provide the first detailed characterization of excitation-induced shifts in optical transition frequencies and demonstrate their exaggeration of nominally homogeneous dephasing rates. The shifts (found to vary in rough proportion to the number of ${\mathrm{Eu}}^{3+}$ ions excited and to be as small as one part in ${10}^{12}$) were identified through their unique signature in specially designed photon-echo experiments. The effects reported may constitute a rather general complication in optical measurements of homogeneous relaxation rates in solids.

DOI: 10.1103/physrevlett.63.78

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Excitation-induced frequency shift probed by stimulated photon echoes

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Physical Review LettersMay 25, 199248 citations

Optical dephasing, hyperfine structure, and hyperfine relaxation associated with the 580.8-nm F07 −5 D0 transition of europium in Eu3+ : Y2 O3

William Randall Babbitt, A. Lezama, THOMAS W. MOSSBERG

Physical review. B, Condensed matterFeb 1, 198970 citations

Photon-echo attenuation in rare-earth-ion-doped crystals

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Physical review. B, Condensed matterDec 15, 199622 citations

Nonequilibrium resonant-phonon-induced excess photon-echo dephasing

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Physical review. B, Condensed matterDec 1, 199212 citations

Dephasing-Rephasing Balancing in Photon Echoes by Excitation Induced Frequency Shifts

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Physical Review LettersMar 4, 199624 citations

Anisotropic Optical-Response of Eu-doped Yttrium Orthosilicate

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NASA University Research Centers Technical Advances in Aeronautics, Space Sciences and Technology, Earth Systems Sciences, Global Hydrology, and EducationFeb 22, 19980 citations

Physical Review Letters

Excess dephasing in photon-echo experiments arising from excitation-induced electronic level shifts

Huang Jin, J.M. Zhang, A. Lezama, THOMAS W. MOSSBERG

Published Jul 3, 1989• 101 citations

Publisher

Abstract

Working on the

^{7}\mathrm{F}_{0}$${\mathrm{\ensuremath{-}}}^{5}$${\mathrm{D}}_{0}

transition of

{\mathrm{Eu}}^{3+}

{\mathrm{Y}}_{2}$${\mathrm{O}}_{3}

, we provide the first detailed characterization of excitation-induced shifts in optical transition frequencies and demonstrate their exaggeration of nominally homogeneous dephasing rates. The shifts (found to vary in rough proportion to the number of

{\mathrm{Eu}}^{3+}

ions excited and to be as small as one part in

{10}^{12}

) were identified through their unique signature in specially designed photon-echo experiments. The effects reported may constitute a rather general complication in optical measurements of homogeneous relaxation rates in solids.

DOI: 10.1103/physrevlett.63.78

Related papers

Excitation-induced frequency shift probed by stimulated photon echoes

Masaharu Mitsunaga, T. Takagahara, Ryuzi Yano +1 more

A stimulated photon-echo study has verified the instantaneous shift (\ensuremath{\le}1 MHz) and subsequent restoration (\ensuremath{\sim}2 ms) of the transition frequency of an impurity ion in a solid when its neighboring ions are exposed to pulsed optical excitation. Experiments were conducted by monitoring the echo intensity for the $^{7}$ ${\mathit{F}}_{0\mathrm{\ensuremath{-}}}^{5}$ ${\mathit{D}}_{0}$ transition of Eu ions in one site of ${\mathrm{Y}}_{2}$ ${\mathrm{SiO}}_{5}$ , while exciting the other site. A photon-echo theory taking account of the stochastic frequency recovery is developed to explain the observations.A stimulated photon-echo study has verified the instantaneous shift (\ensuremath{\le}1 MHz) and subsequent restoration (\ensuremath{\sim}2 ms) of the transition frequency of an impurity ion in a solid when its neighboring ions are exposed to pulsed optical excitation. Experiments were conducted by monitoring the echo intensity for the $^{7}$${\mathit{F}}_{0\mathrm{\ensuremath{-}}}^{5}$${\mathit{D}}_{0}$ transition of Eu ions in one site of ${\mathrm{Y}}_{2}$${\mathrm{SiO}}_{5}$, while exciting the other site. A photon-echo theory taking account of the stochastic frequency recovery is developed to explain the observations.

Physical Review LettersMay 25, 199248 citations

Optical dephasing, hyperfine structure, and hyperfine relaxation associated with the 580.8-nm F07 −5 D0 transition of europium in Eu3+ : Y2 O3

William Randall Babbitt, A. Lezama, THOMAS W. MOSSBERG

We have employed spectral-hole-burning, coherent-transient, and optical-rf double-resonance techniques to measure various parameters associated with the 580.8-nm $^{7}\mathrm{F}_{0}$ ${\mathrm{\ensuremath{-}}}^{5}$ ${\mathrm{D}}_{0}$ transition of ${\mathrm{Eu}}^{3+}$ doped into ${\mathrm{Y}}_{2}$ ${\mathrm{O}}_{3}$ . In particular, we have measured the hyperfine splittings of the terminal levels (for both $^{151}\mathrm{Eu}$ and $^{153}\mathrm{Eu}$ ), an effective thermalization rate of the ground-state ${(}^{7}$ ${\mathrm{F}}_{0}$ ) hyperfine manifold over the temperature range of \ensuremath{\simeq}4--15 K, and the homogeneous linewidth of the optical transition over the range of \ensuremath{\simeq}14--35 K. Large ratios of inhomogeneous to homogeneous linewidth at elevated temperatures ( ${10}^{3}$ at 25 K) and long ground-state hyperfine thermalization times (>30 h at 4 K) make this an interesting crystal in the context of spectrally addressable optical memories.We have employed spectral-hole-burning, coherent-transient, and optical-rf double-resonance techniques to measure various parameters associated with the 580.8-nm $^{7}\mathrm{F}_{0}$${\mathrm{\ensuremath{-}}}^{5}$${\mathrm{D}}_{0}$ transition of ${\mathrm{Eu}}^{3+}$ doped into ${\mathrm{Y}}_{2}$${\mathrm{O}}_{3}$. In particular, we have measured the hyperfine splittings of the terminal levels (for both $^{151}\mathrm{Eu}$ and $^{153}\mathrm{Eu}$), an effective thermalization rate of the ground-state ${(}^{7}$${\mathrm{F}}_{0}$) hyperfine manifold over the temperature range of \ensuremath{\simeq}4--15 K, and the homogeneous linewidth of the optical transition over the range of \ensuremath{\simeq}14--35 K. Large ratios of inhomogeneous to homogeneous linewidth at elevated temperatures (${10}^{3}$ at 25 K) and long ground-state hyperfine thermalization times (>30 h at 4 K) make this an interesting crystal in the context of spectrally addressable optical memories.

Physical review. B, Condensed matterFeb 1, 198970 citations

Photon-echo attenuation in rare-earth-ion-doped crystals

Stefan B. Altner, G. Zumofen, Urs P. Wild +1 more

We study the optical properties of rare-earth-ion-doped inorganic crystals with an emphasis on the dependence of two-pulse photon echoes on the excitation density in the system. The experimental investigations concentrate on ${\mathrm{Pr}}^{3+}$ : ${\mathrm{Nd}}^{3+}$ : ${\mathrm{Eu}}^{3+}$ codoped ${\mathrm{Y}}_{2}$ Si ${\mathrm{O}}_{5}$ and YAl ${\mathrm{O}}_{3}$ crystals at low temperatures. With two pulses of one laser the echo is induced in one ion species and with a third, "scrambler" pulse of a second laser another species is excited. These scrambler excitations lead to a dephasing and thus to an echo attenuation which depends on the strength, frequency, and time of the scrambler pulse. The spectral sensitivity of the echo attenuation is used for a spectroscopic technique: "photon-echo attenuation spectroscopy." As a function of the delay time ${t}_{s}$ between the scrambler pulse and the onset of the two-pulse echo sequence the attenuation shows a very specific behavior dictated by the excitation-induced frequency shifts (EFS's). For ${t}_{s}$ between the two echo-inducing pulses the echo intensity is partially regained by the "dephasing-rephasing balancing" of the reversible EFS's. For the theoretical description a stochastic model is introduced and the dephasing by excitation-induced lattice vibrations and by EFS's are analyzed in detail. The present results are discussed in the light of previous experimental and theoretical investigations.We study the optical properties of rare-earth-ion-doped inorganic crystals with an emphasis on the dependence of two-pulse photon echoes on the excitation density in the system. The experimental investigations concentrate on ${\mathrm{Pr}}^{3+}$:${\mathrm{Nd}}^{3+}$:${\mathrm{Eu}}^{3+}$ codoped ${\mathrm{Y}}_{2}$Si${\mathrm{O}}_{5}$ and YAl${\mathrm{O}}_{3}$ crystals at low temperatures. With two pulses of one laser the echo is induced in one ion species and with a third, "scrambler" pulse of a second laser another species is excited. These scrambler excitations lead to a dephasing and thus to an echo attenuation which depends on the strength, frequency, and time of the scrambler pulse. The spectral sensitivity of the echo attenuation is used for a spectroscopic technique: "photon-echo attenuation spectroscopy." As a function of the delay time ${t}_{s}$ between the scrambler pulse and the onset of the two-pulse echo sequence the attenuation shows a very specific behavior dictated by the excitation-induced frequency shifts (EFS's). For ${t}_{s}$ between the two echo-inducing pulses the echo intensity is partially regained by the "dephasing-rephasing balancing" of the reversible EFS's. For the theoretical description a stochastic model is introduced and the dephasing by excitation-induced lattice vibrations and by EFS's are analyzed in detail. The present results are discussed in the light of previous experimental and theoretical investigations.

Physical review. B, Condensed matterDec 15, 199622 citations

Nonequilibrium resonant-phonon-induced excess photon-echo dephasing

Yue Bai, Ravinder Kachru

We demonstrate that the excitation-induced excess dephasing of photon echoes in ${\mathrm{Pr}}^{3+}$ : ${\mathrm{YA}1\mathrm{O}}_{3}$ ${(}^{3}$ ${\mathrm{H}}_{4}$ ${\mathrm{\ensuremath{-}}}^{1}$ ${\mathrm{D}}_{2}$ ) is predominantly induced by the 51-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ resonant phonons associated with nonradiative relaxations of the excited ions. Instantaneous diffusion via direct ion-ion coupling is found to be much less important. The dephasing mechanism discussed should be applicable to all other systems where the relaxation of excited states involves nonradiative processes.We demonstrate that the excitation-induced excess dephasing of photon echoes in ${\mathrm{Pr}}^{3+}$:${\mathrm{YA}1\mathrm{O}}_{3}$${(}^{3}$${\mathrm{H}}_{4}$${\mathrm{\ensuremath{-}}}^{1}$${\mathrm{D}}_{2}$) is predominantly induced by the 51-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ resonant phonons associated with nonradiative relaxations of the excited ions. Instantaneous diffusion via direct ion-ion coupling is found to be much less important. The dephasing mechanism discussed should be applicable to all other systems where the relaxation of excited states involves nonradiative processes.

Physical review. B, Condensed matterDec 1, 199212 citations

Dephasing-Rephasing Balancing in Photon Echoes by Excitation Induced Frequency Shifts

Stefan B. Altner, Masaharu Mitsunaga, G. Zumofen +1 more

The excitation dephasing in solids resulting from the interaction with neighboring species' excitations is investigated. The frequency shifts due to these interactions are identified by the observation of partial dephasing-rephasing balancing in bichromatic photon-echo experiments applied to rare-earth ion doped crystals. The experimental observations are in good agreement with the predictions obtained from a model which accounts for the disorder in the crystal and for the stochastic nature of the excitations.The excitation dephasing in solids resulting from the interaction with neighboring species' excitations is investigated. The frequency shifts due to these interactions are identified by the observation of partial dephasing-rephasing balancing in bichromatic photon-echo experiments applied to rare-earth ion doped crystals. The experimental observations are in good agreement with the predictions obtained from a model which accounts for the disorder in the crystal and for the stochastic nature of the excitations.

Physical Review LettersMar 4, 199624 citations

Anisotropic Optical-Response of Eu-doped Yttrium Orthosilicate

Huimin Liu, M. L. Santiago, Weiyi Jia +1 more

Eu-doped yttrium orthosilicate (Eu(3+) : Y2SiO5) had been a subject being investigated for coherent time-domain optical memory and information processing applications since its ultraslow optical dephasing was discovered several years ago. In this crystal the weakly allowed (7)F0 - (5)D0 transition of europium ions exhibits a sufficient long dephasing time and no spectral difli.usion on a time scale of several hours at low temperature, thus an information pattern or data can be stored as a population grating in the ground state hyperfine levels. On the other hand, the study on photon-echo relaxation shows that the dephasing time T2 of Eu (3+) and other rare-earth ions doped YAG, YAlO3 strongly depends on the intensity of the excitation pulses. In Eu (3+) :YAlO3, an exponential decay of photon-echo with T2 = 53 microseconds if the excitation pulses are weak (5 vJ/pulse) was observed. However, when the excitation pulses are strong (80 pJ/pulse) they observed a much shortened T2 with a highly nonexponential decay pattern. The conclusion they derived is that the intensity-dependent dephasing rate effects are quite general, and it depends on how much the excitation intensity varies. In this paper we use transient grating formation technique showing that a temporal lattice distortion may only occur along crystal c axis, caused by EU (3+) excitation. At high excitation level the produced exciton in conduction band may also couple to the dynamical lattice relaxation process, giving rise to an apparently much shortened dephasing time.Eu-doped yttrium orthosilicate (Eu(3+) : Y2SiO5) had been a subject being investigated for coherent time-domain optical memory and information processing applications since its ultraslow optical dephasing was discovered several years ago. In this crystal the weakly allowed (7)F0 - (5)D0 transition of europium ions exhibits a sufficient long dephasing time and no spectral difli.usion on a time scale of several hours at low temperature, thus an information pattern or data can be stored as a population grating in the ground state hyperfine levels. On the other hand, the study on photon-echo relaxation shows that the dephasing time T2 of Eu (3+) and other rare-earth ions doped YAG, YAlO3 strongly depends on the intensity of the excitation pulses. In Eu (3+) :YAlO3, an exponential decay of photon-echo with T2 = 53 microseconds if the excitation pulses are weak (5 vJ/pulse) was observed. However, when the excitation pulses are strong (80 pJ/pulse) they observed a much shortened T2 with a highly nonexponential decay pattern. The conclusion they derived is that the intensity-dependent dephasing rate effects are quite general, and it depends on how much the excitation intensity varies. In this paper we use transient grating formation technique showing that a temporal lattice distortion may only occur along crystal c axis, caused by EU (3+) excitation. At high excitation level the produced exciton in conduction band may also couple to the dynamical lattice relaxation process, giving rise to an apparently much shortened dephasing time.

NASA University Research Centers Technical Advances in Aeronautics, Space Sciences and Technology, Earth Systems Sciences, Global Hydrology, and EducationFeb 22, 19980 citations

Working on the

^{7}\mathrm{F}_{0}$${\mathrm{\ensuremath{-}}}^{5}$${\mathrm{D}}_{0}

transition of

{\mathrm{Eu}}^{3+}

{\mathrm{Y}}_{2}$${\mathrm{O}}_{3}

{\mathrm{Eu}}^{3+}

ions excited and to be as small as one part in

{10}^{12}

^{7}

${\mathit{F}}_{0\mathrm{\ensuremath{-}}}^{5}$

{\mathit{D}}_{0}

transition of Eu ions in one site of

{\mathrm{Y}}_{2}

{\mathrm{SiO}}_{5}

, while exciting the other site. A photon-echo theory taking account of the stochastic frequency recovery is developed to explain the observations.

We have employed spectral-hole-burning, coherent-transient, and optical-rf double-resonance techniques to measure various parameters associated with the 580.8-nm

^{7}\mathrm{F}_{0}

${\mathrm{\ensuremath{-}}}^{5}$

{\mathrm{D}}_{0}

transition of

{\mathrm{Eu}}^{3+}

doped into

{\mathrm{Y}}_{2}

{\mathrm{O}}_{3}

. In particular, we have measured the hyperfine splittings of the terminal levels (for both

^{151}\mathrm{Eu}

and

^{153}\mathrm{Eu}

), an effective thermalization rate of the ground-state

{(}^{7}

{\mathrm{F}}_{0}

) hyperfine manifold over the temperature range of \ensuremath{\simeq}4--15 K, and the homogeneous linewidth of the optical transition over the range of \ensuremath{\simeq}14--35 K. Large ratios of inhomogeneous to homogeneous linewidth at elevated temperatures (

{10}^{3}

at 25 K) and long ground-state hyperfine thermalization times (>30 h at 4 K) make this an interesting crystal in the context of spectrally addressable optical memories.

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

{\mathrm{Nd}}^{3+}

{\mathrm{Eu}}^{3+}

codoped

{\mathrm{Y}}_{2}

{\mathrm{O}}_{5}

and YAl

{\mathrm{O}}_{3}

crystals at low temperatures. With two pulses of one laser the echo is induced in one ion species and with a third, "scrambler" pulse of a second laser another species is excited. These scrambler excitations lead to a dephasing and thus to an echo attenuation which depends on the strength, frequency, and time of the scrambler pulse. The spectral sensitivity of the echo attenuation is used for a spectroscopic technique: "photon-echo attenuation spectroscopy." As a function of the delay time

{t}_{s}

between the scrambler pulse and the onset of the two-pulse echo sequence the attenuation shows a very specific behavior dictated by the excitation-induced frequency shifts (EFS's). For

{t}_{s}

between the two echo-inducing pulses the echo intensity is partially regained by the "dephasing-rephasing balancing" of the reversible EFS's. For the theoretical description a stochastic model is introduced and the dephasing by excitation-induced lattice vibrations and by EFS's are analyzed in detail. The present results are discussed in the light of previous experimental and theoretical investigations.

We demonstrate that the excitation-induced excess dephasing of photon echoes in

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

{\mathrm{YA}1\mathrm{O}}_{3}

{(}^{3}

{\mathrm{H}}_{4}

${\mathrm{\ensuremath{-}}}^{1}$

{\mathrm{D}}_{2}

) is predominantly induced by the 51-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ resonant phonons associated with nonradiative relaxations of the excited ions. Instantaneous diffusion via direct ion-ion coupling is found to be much less important. The dephasing mechanism discussed should be applicable to all other systems where the relaxation of excited states involves nonradiative processes.