A reflectivity of 45%of the self-pumped phase-conjugate wave in (K_(0.5)Na_(0.5))_(0.2)(Sr_(0.75)Ba_(0.25))_(0.9)Nb_(2)0_(6)-Cn crystal at the environmental temperature T~70℃ has been obtained.The temperature effect ...A reflectivity of 45%of the self-pumped phase-conjugate wave in (K_(0.5)Na_(0.5))_(0.2)(Sr_(0.75)Ba_(0.25))_(0.9)Nb_(2)0_(6)-Cn crystal at the environmental temperature T~70℃ has been obtained.The temperature effect in this kind of self-pumped phase-conjugator is studied.展开更多
A differential scanning calorimetric(DSC)study of the crystal Li_(0.02)Na_(0.98)NbO_(3) was carried out in the temperature range from 120 to 300K.The specific heat changes anomalously at about 180K on cooling and abou...A differential scanning calorimetric(DSC)study of the crystal Li_(0.02)Na_(0.98)NbO_(3) was carried out in the temperature range from 120 to 300K.The specific heat changes anomalously at about 180K on cooling and about 260K on heating,implying a first order phase transition.The heat of transition ΔQ=(212±50)J/mol and the corresponding change in entropy AS=0.82J/mol.K.The thermal hysteresis of this transition is about 80K,in agreement with that previously obtained from the dielectric and pyroelectric measurements.展开更多
The mechanism for the high-performance KNSBN:Cu crystal self-pumped phase-conjugator is first put forward in this letter as no-loop photorefractive self-bending succesive four-wave mixing interaction.And the photore f...The mechanism for the high-performance KNSBN:Cu crystal self-pumped phase-conjugator is first put forward in this letter as no-loop photorefractive self-bending succesive four-wave mixing interaction.And the photore fractive backscattering amplification was found to play a very important role in it.展开更多
Potasium sodium lead barium niobate KNPBN crystals have been grown successfully by flux method.The dielectric constant along the polar axis was measured at 50 kHz as a function of temperature in the range of 0 to 400...Potasium sodium lead barium niobate KNPBN crystals have been grown successfully by flux method.The dielectric constant along the polar axis was measured at 50 kHz as a function of temperature in the range of 0 to 400℃.The flux system,diffuse phase transition and optical absorption were also discussed.展开更多
Two coherent or incoherent stable self-pumped phase conjugations have been obtained simultaneously in a Ce-doped(K_(0.5)Na_(0.5))_(2y)(Sr_(0.61)Ba_(0.39))_(1-y) Nb_(2)O_(6)(KNSBN)crystal by using two mutually coherent...Two coherent or incoherent stable self-pumped phase conjugations have been obtained simultaneously in a Ce-doped(K_(0.5)Na_(0.5))_(2y)(Sr_(0.61)Ba_(0.39))_(1-y) Nb_(2)O_(6)(KNSBN)crystal by using two mutually coherent input beams from a He-Ne laser,and energy translation from one beam to another induces self-pumped phase conjugative reflectivity of one beam above 100%.展开更多
This paper reports the growth of pqre and Na,K modified lead barium niobate crystals and the measurement of their dielectric and structure properties.Exprimental results show that both pure and Na,K modified lead bari...This paper reports the growth of pqre and Na,K modified lead barium niobate crystals and the measurement of their dielectric and structure properties.Exprimental results show that both pure and Na,K modified lead barium niobate crystals have growth striations.All the crystals belong to 4mm point group of tetragonal system at room temperature.Their Curie temperature are 379℃,389℃ and 473℃,respectively.展开更多
Striation-free LiBa_(2)Nb_(5)O_(15)(LBN)single crystal of good optical quality has been grown by Czochralski method.The crystal growth and dielectric,structural,spectral properties of LBN were measured.Experimental re...Striation-free LiBa_(2)Nb_(5)O_(15)(LBN)single crystal of good optical quality has been grown by Czochralski method.The crystal growth and dielectric,structural,spectral properties of LBN were measured.Experimental results show that LBN single crystal belongs to tetragonal tungsten bronze structure at room temperature.Experiments carried out with LBN powder samples have shown that this crystal has good second harmonic generation effect.At room temperature,the dielectric constant ε_(33) is about 87 and Curie temperature T_(c),is about 586℃.A very ideal uniaxial conoscope image can be observed in LBN single crystal under polarizing microscope.In the range of 600 to 2600nm,the transmission of single crystal is about 75%.展开更多
The image intensity inversion operation was succeeded by using the new type KNSBN.Cu crystal self-pumped phase-conjugate mirror.The new phase-conjugator was demonstrated to have the reguired specifications for this op...The image intensity inversion operation was succeeded by using the new type KNSBN.Cu crystal self-pumped phase-conjugate mirror.The new phase-conjugator was demonstrated to have the reguired specifications for this optical processing application.展开更多
The Cu-doped'KNSBN crystals have been grown.The self-pumped phase conjugate mirrors of Cu-doped KNSBN crystals have been demonstrated.The phase conjugate reflectivity reaches as high as 68% for the crystal with 0....The Cu-doped'KNSBN crystals have been grown.The self-pumped phase conjugate mirrors of Cu-doped KNSBN crystals have been demonstrated.The phase conjugate reflectivity reaches as high as 68% for the crystal with 0.04 wt.%Cu-doped.The phase conjugate reflectivity and its response time were also measured as a function of the argon-ion laser wavelengths.展开更多
Edge enhancement has been performed in Ce-doped(K_(0.5)Na_(0.5))_(2y)(Sr_(0.61)Ba_(0.39))_(1-y)Nb_(2)O_(6)(KNSBN)crystal at 633nm with low incident-light intensities 10^(-3)W/cm^(2).We calculated the expected images w...Edge enhancement has been performed in Ce-doped(K_(0.5)Na_(0.5))_(2y)(Sr_(0.61)Ba_(0.39))_(1-y)Nb_(2)O_(6)(KNSBN)crystal at 633nm with low incident-light intensities 10^(-3)W/cm^(2).We calculated the expected images which show good agreement with the images that we have experimentally observed.展开更多
This paper reports the growth and two-wave coupling properties of(K_(0.5)-Na_(0.5))2z(Sr_(0.75)Ba_(0.25))_(1-z)Nb_(2)O_(6)(z=0.1,0.05 and 0.03)crystals.Comparing to the others,the crystal at z=0.05 has shorter respons...This paper reports the growth and two-wave coupling properties of(K_(0.5)-Na_(0.5))2z(Sr_(0.75)Ba_(0.25))_(1-z)Nb_(2)O_(6)(z=0.1,0.05 and 0.03)crystals.Comparing to the others,the crystal at z=0.05 has shorter response time and larger two-wave coupling gain coefficient.The gain coefficient of it surpasses that of SBN:Ce.展开更多
Self-pumped phase conjugation has been observed in Ce-doped(K_(0.5)Na_(0.5))2y(Sr_(0.61)Ba_(0.39))_(1-y)Nb_(2)O_(6)(KNSBN)crystal at 633nm by using He-Ne laser.The phase conjugate reflectivity as high as 40% was measu...Self-pumped phase conjugation has been observed in Ce-doped(K_(0.5)Na_(0.5))2y(Sr_(0.61)Ba_(0.39))_(1-y)Nb_(2)O_(6)(KNSBN)crystal at 633nm by using He-Ne laser.The phase conjugate reflectivity as high as 40% was measured.The reflectivity as function of incident angles and the relation of response time to the incident intensities were studied experimentally.展开更多
The optical quality Pb^(1-x)Ba_(x)Nb_(2)O_(6) single crystals have been grown by Czochraski method from the melt.Their structure,dielectric,ferroelectric properties were studied.Transmission spectra,two-wave maxing pr...The optical quality Pb^(1-x)Ba_(x)Nb_(2)O_(6) single crystals have been grown by Czochraski method from the melt.Their structure,dielectric,ferroelectric properties were studied.Transmission spectra,two-wave maxing properties were measured.This crystal will be an available material for photorefractive applications.展开更多
Tb-doped SBN crystals were prepared by the Czochralski technique.Their dielectric,ferroelectric,and pyroelectric properties were studied.A low temperature phase transition between two polar phases was revealed by the ...Tb-doped SBN crystals were prepared by the Czochralski technique.Their dielectric,ferroelectric,and pyroelectric properties were studied.A low temperature phase transition between two polar phases was revealed by the anomalies of the dielectric and pyroelectric properties;the polar axis changes its direction during this transition.The point group of the low temperature phase may be mm2,m or 1.展开更多
Cd_(x)(Sr_(0.61)Ba_(0.39))_(1-x)Nb_(2)O_(6)(CdSBN)crystals have been grown successfully by Czochralski technique.The difficulty in crystal growth increased with the increase of the crystal diameter.Macroscopic defects...Cd_(x)(Sr_(0.61)Ba_(0.39))_(1-x)Nb_(2)O_(6)(CdSBN)crystals have been grown successfully by Czochralski technique.The difficulty in crystal growth increased with the increase of the crystal diameter.Macroscopic defects,such as striations and crackings were observed in some crystals.Temperature dependence of dielectric constant ε′γ3 and pyroelectric coefficient P were studied.The relationship between grown behavior and melt compositions was also discussed.展开更多
Subbarao^(1) discovered the first ferroelectrie tungsten bronze solid solution Pb_(1-x)Ba_(x )Nb_(2)O_(6)・This system has a morphotropic phase boundary(MPB)found at x=0.37.The electro-optic properties for crystai comp...Subbarao^(1) discovered the first ferroelectrie tungsten bronze solid solution Pb_(1-x)Ba_(x )Nb_(2)O_(6)・This system has a morphotropic phase boundary(MPB)found at x=0.37.The electro-optic properties for crystai compositions close to MPB regions can be at least 5 to 10 times better than the current best materials.Chen et al.reported the Czochralski single crystal growth technique and fundamental properties of PBN and LNPBN.The results show that most of the crystals grown were lack of Pb due to the volatilization of PbO during crystal growth.展开更多
基金Supported by the National Natural Science Foundation of China.
文摘A reflectivity of 45%of the self-pumped phase-conjugate wave in (K_(0.5)Na_(0.5))_(0.2)(Sr_(0.75)Ba_(0.25))_(0.9)Nb_(2)0_(6)-Cn crystal at the environmental temperature T~70℃ has been obtained.The temperature effect in this kind of self-pumped phase-conjugator is studied.
文摘A differential scanning calorimetric(DSC)study of the crystal Li_(0.02)Na_(0.98)NbO_(3) was carried out in the temperature range from 120 to 300K.The specific heat changes anomalously at about 180K on cooling and about 260K on heating,implying a first order phase transition.The heat of transition ΔQ=(212±50)J/mol and the corresponding change in entropy AS=0.82J/mol.K.The thermal hysteresis of this transition is about 80K,in agreement with that previously obtained from the dielectric and pyroelectric measurements.
基金Supported by the National Natural Science Foundation of ChinaTianjin Science Foundation for Youth.
文摘The mechanism for the high-performance KNSBN:Cu crystal self-pumped phase-conjugator is first put forward in this letter as no-loop photorefractive self-bending succesive four-wave mixing interaction.And the photore fractive backscattering amplification was found to play a very important role in it.
文摘Potasium sodium lead barium niobate KNPBN crystals have been grown successfully by flux method.The dielectric constant along the polar axis was measured at 50 kHz as a function of temperature in the range of 0 to 400℃.The flux system,diffuse phase transition and optical absorption were also discussed.
文摘Two coherent or incoherent stable self-pumped phase conjugations have been obtained simultaneously in a Ce-doped(K_(0.5)Na_(0.5))_(2y)(Sr_(0.61)Ba_(0.39))_(1-y) Nb_(2)O_(6)(KNSBN)crystal by using two mutually coherent input beams from a He-Ne laser,and energy translation from one beam to another induces self-pumped phase conjugative reflectivity of one beam above 100%.
文摘This paper reports the growth of pqre and Na,K modified lead barium niobate crystals and the measurement of their dielectric and structure properties.Exprimental results show that both pure and Na,K modified lead barium niobate crystals have growth striations.All the crystals belong to 4mm point group of tetragonal system at room temperature.Their Curie temperature are 379℃,389℃ and 473℃,respectively.
文摘Striation-free LiBa_(2)Nb_(5)O_(15)(LBN)single crystal of good optical quality has been grown by Czochralski method.The crystal growth and dielectric,structural,spectral properties of LBN were measured.Experimental results show that LBN single crystal belongs to tetragonal tungsten bronze structure at room temperature.Experiments carried out with LBN powder samples have shown that this crystal has good second harmonic generation effect.At room temperature,the dielectric constant ε_(33) is about 87 and Curie temperature T_(c),is about 586℃.A very ideal uniaxial conoscope image can be observed in LBN single crystal under polarizing microscope.In the range of 600 to 2600nm,the transmission of single crystal is about 75%.
文摘The image intensity inversion operation was succeeded by using the new type KNSBN.Cu crystal self-pumped phase-conjugate mirror.The new phase-conjugator was demonstrated to have the reguired specifications for this optical processing application.
文摘The Cu-doped'KNSBN crystals have been grown.The self-pumped phase conjugate mirrors of Cu-doped KNSBN crystals have been demonstrated.The phase conjugate reflectivity reaches as high as 68% for the crystal with 0.04 wt.%Cu-doped.The phase conjugate reflectivity and its response time were also measured as a function of the argon-ion laser wavelengths.
文摘Edge enhancement has been performed in Ce-doped(K_(0.5)Na_(0.5))_(2y)(Sr_(0.61)Ba_(0.39))_(1-y)Nb_(2)O_(6)(KNSBN)crystal at 633nm with low incident-light intensities 10^(-3)W/cm^(2).We calculated the expected images which show good agreement with the images that we have experimentally observed.
文摘This paper reports the growth and two-wave coupling properties of(K_(0.5)-Na_(0.5))2z(Sr_(0.75)Ba_(0.25))_(1-z)Nb_(2)O_(6)(z=0.1,0.05 and 0.03)crystals.Comparing to the others,the crystal at z=0.05 has shorter response time and larger two-wave coupling gain coefficient.The gain coefficient of it surpasses that of SBN:Ce.
文摘Self-pumped phase conjugation has been observed in Ce-doped(K_(0.5)Na_(0.5))2y(Sr_(0.61)Ba_(0.39))_(1-y)Nb_(2)O_(6)(KNSBN)crystal at 633nm by using He-Ne laser.The phase conjugate reflectivity as high as 40% was measured.The reflectivity as function of incident angles and the relation of response time to the incident intensities were studied experimentally.
基金Supported by the Natural Science Foundation of China.
文摘The optical quality Pb^(1-x)Ba_(x)Nb_(2)O_(6) single crystals have been grown by Czochraski method from the melt.Their structure,dielectric,ferroelectric properties were studied.Transmission spectra,two-wave maxing properties were measured.This crystal will be an available material for photorefractive applications.
文摘Tb-doped SBN crystals were prepared by the Czochralski technique.Their dielectric,ferroelectric,and pyroelectric properties were studied.A low temperature phase transition between two polar phases was revealed by the anomalies of the dielectric and pyroelectric properties;the polar axis changes its direction during this transition.The point group of the low temperature phase may be mm2,m or 1.
文摘Cd_(x)(Sr_(0.61)Ba_(0.39))_(1-x)Nb_(2)O_(6)(CdSBN)crystals have been grown successfully by Czochralski technique.The difficulty in crystal growth increased with the increase of the crystal diameter.Macroscopic defects,such as striations and crackings were observed in some crystals.Temperature dependence of dielectric constant ε′γ3 and pyroelectric coefficient P were studied.The relationship between grown behavior and melt compositions was also discussed.
基金supported by the Science Fund of the Chinese Academy of Sciences.
文摘Subbarao^(1) discovered the first ferroelectrie tungsten bronze solid solution Pb_(1-x)Ba_(x )Nb_(2)O_(6)・This system has a morphotropic phase boundary(MPB)found at x=0.37.The electro-optic properties for crystai compositions close to MPB regions can be at least 5 to 10 times better than the current best materials.Chen et al.reported the Czochralski single crystal growth technique and fundamental properties of PBN and LNPBN.The results show that most of the crystals grown were lack of Pb due to the volatilization of PbO during crystal growth.
