The neodymium ions doped gadolinium vanadate (Nd∶GdVO_4) single crystals were successfully grown by Czochralski method. Chemical etching technique was used to reveal the dislocation structure of the crystals. An aver...The neodymium ions doped gadolinium vanadate (Nd∶GdVO_4) single crystals were successfully grown by Czochralski method. Chemical etching technique was used to reveal the dislocation structure of the crystals. An average dislocation density of (100) plane is 600 pits/mm 2. The crystal-morphology can be used to determine crystal orientation accurately with simple optical method.展开更多
The thermal lensing effect generated in an end-pumped lightly doped Nd:GdVO4 crystal was found to be considerably weaker than that in Nd:YVO4 having the same Nd3+ concentration. Consequently, the laser performance of ...The thermal lensing effect generated in an end-pumped lightly doped Nd:GdVO4 crystal was found to be considerably weaker than that in Nd:YVO4 having the same Nd3+ concentration. Consequently, the laser performance of Nd:GdVO4 at high pump powers over 20 W was found to be superior to that of Nd:YVO4. TEM00 mode cw radiation of 14.3 W at 1.06μm was achieved with an optical conversion efficiency of 55%, and average slope efficiency of 62%.展开更多
Objective:The properties of Nd:GdVO4 laser crystals were studied in application of all-solid laser with LD pumped.Method:We adopted sand wich structural Nd:YVO4 laser crystals experimental devices separately.Results:...Objective:The properties of Nd:GdVO4 laser crystals were studied in application of all-solid laser with LD pumped.Method:We adopted sand wich structural Nd:YVO4 laser crystals experimental devices separately.Results:As to Nd:YVO4 crystal,1.2W continuous laser output at 1064nm was ac-quired with the optical-to-optical transition efficiency of 30%.And as to Nd:GdVO4,1.8W continuous laser out-put at 1064nm was acquired with the optical-to-optical efficiency of 47.2%.Conclusion:All-solid laser is of simple and compact structure,long lifetime,low cost and high efficiency that it will be extensively applied to laser bioengineering,laser environmental monitoring and so on.And comparing the properties of Nd:GdVO4 to that of Nd:YVO4,Nd:GdVO4 would be a more promising all-solid laser crystal.展开更多
A diode-end-pumped electro-optic (EO) Q-switched adhesive-free bond composite Nd:YVO4 laser operating at a repetition rate of 200 kHz is reported.A pair of RbTiOPO4 (RTP) crystals are used as a high repetition EO Q-sw...A diode-end-pumped electro-optic (EO) Q-switched adhesive-free bond composite Nd:YVO4 laser operating at a repetition rate of 200 kHz is reported.A pair of RbTiOPO4 (RTP) crystals are used as a high repetition EO Q-switch.At the repetition rate of 200kHz,the maximum average output power of 11.8 W at wavelength 1064 nm and full width at half maximum of pulses of 16.65ns are achieved at an incident pump power of 27 W,corresponding to an optical conversion efficiency of 43.7% and a slope efficiency of 44.6%,respectively.To the best of our knowledge,this is the highest repetition rate reported on the EO Q-switched laser by using RTP crystals.展开更多
The absorption and emission spectra of the YVO4 single crystal co-doped with 1 at.% Nd^3＋ and 1 at.% Yb^3＋ are investigated. The efficient Nd^3＋ → Yb^3＋ energy transfer and the back transfer （Yb^3＋ → Nd^3＋） ...The absorption and emission spectra of the YVO4 single crystal co-doped with 1 at.% Nd^3＋ and 1 at.% Yb^3＋ are investigated. The efficient Nd^3＋ → Yb^3＋ energy transfer and the back transfer （Yb^3＋ → Nd^3＋） are observed at room temperature. The fluorescence lifetime of the 4F3/2 level of Nd^3＋ in Nd,Yb：YVO4 is measured under 808 nm laser light excitation. The efficiency of Nd^3＋ → Yb^3＋ energy transfer in YVO4 is determined to be about 34%.展开更多
This paper reports the growth, X-ray diffraction and spectroscopy of Nd3＋：Sr3Gd2（BO3）4 crystal. A Nd3＋：Sr3Gd2（BO3）4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3＋...This paper reports the growth, X-ray diffraction and spectroscopy of Nd3＋：Sr3Gd2（BO3）4 crystal. A Nd3＋：Sr3Gd2（BO3）4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3＋：Sr3Gd2（BO3）4 crystal belongs to the orthorhombic system, space group Pnma （D2h） with a = 0.7401, b = 1.604 and c = 0.8755 nm. The absorption and emission spectra of Nd3＋：Sr3Gd2（BO3）4 were investigated. The absorption cross section oa is 3.11 × 10^-20cm2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm. The luminescence lifetime τf is 51.7 μs. The emission cross section oc at 1064 nm wavelength is 1.09 × 10^-19 cm2.展开更多
The passively Q-switched and mode-locked（QML） characteristics in a diode-pumped Nd∶GdVO4 laser with Cr4+∶YAG saturable absorbers have been demonstrated. A maximum average output power of 710mW has been obtained ...The passively Q-switched and mode-locked（QML） characteristics in a diode-pumped Nd∶GdVO4 laser with Cr4+∶YAG saturable absorbers have been demonstrated. A maximum average output power of 710mW has been obtained in the QML laser. The maximum energy of a single Q-switched pulse is 52.5μJ, with the corresponding pulse width of 30ns and the peak power of 1.75kW, at the incident pump power of 7.75W. The repetition rates of the Q-switched envelope and the mode-locked laser pulse are 16.7kHz and 680MHz, respectively.展开更多
Nd:NaBi(WO_4)_2 crystals (Nd:NBW) were grown by Czochralski method. The pulling rate is 0.3 mm·h (-1),and the rotational speed of Nd:NBW crystal is 2 r·min (-1). The components of this single crystal were de...Nd:NaBi(WO_4)_2 crystals (Nd:NBW) were grown by Czochralski method. The pulling rate is 0.3 mm·h (-1),and the rotational speed of Nd:NBW crystal is 2 r·min (-1). The components of this single crystal were determined by X-ray diffractions,and its corresponding properties were described from thermal gravity and differential thermal analysis experiments. The absorption cross-sections were calculated. The emission band of Nd:NBW crystal was obtained from its luminous spectrum.展开更多
Synthesis of polycrystalline Nd：Sr0.95Ba0.05WO4 by means of liquid-and solid-phase reaction was reported.X-ray powder diffraction results showed that the as-grown Sr0.95Ba0.05WO4 and Nd：Sr0.95Ba0.05WO4 single crysta...Synthesis of polycrystalline Nd：Sr0.95Ba0.05WO4 by means of liquid-and solid-phase reaction was reported.X-ray powder diffraction results showed that the as-grown Sr0.95Ba0.05WO4 and Nd：Sr0.95Ba0.05WO4 single crystals belonged to tetragonal system and I41/a space group.Transparent Nd：Sr0.95Ba0.05WO4 single crystal could be obtained along c-axis by Czochralski method from the synthesized polycrys-talline material.As the transmittance of Sr0.95Ba.005WO4 single crystal could reach 80%, Nd3＋ ion was adopted to be doped into the single crystal.Spontaneous Raman spectrums of polycrystalline material and single crystal were measured by RERKZN-ELMER2000 and JY-HR800.By using X-ray fluorescence method, the effective segregation coefficients of Nd, Ba, Sr, and W elements in Sr0.95Ba.005WO4 single crystal were estimated as 0.844（0.745）, 0.44, 1.09, and 0.95, respectively.The segregation coefficients of Nd in Sr0.95Ba0.05WO4 were higher than that in BaWO4, and this is as better as a Raman laser crystal.展开更多
The crystal structure of di-hydroxyisobutyrate)diaquo neodymium nitrate Nd(C_4H_7O_3)_2NO_32H_2O was determined by X-ray diffraction analysis. It belongs to monoclinic,space group C2/C,with cell dimensionsa=8.996(1), ...The crystal structure of di-hydroxyisobutyrate)diaquo neodymium nitrate Nd(C_4H_7O_3)_2NO_32H_2O was determined by X-ray diffraction analysis. It belongs to monoclinic,space group C2/C,with cell dimensionsa=8.996(1), b=8.601(1),c=21.111(3),β=92.38°,V=1632.O,Z=4,D_c=1.83g/cm^3.Crystal structure has been refined by full-matrix least-square techniques giving a final R value of 0.036.The neodymium atom is coordinated to eight oxygen atoms.The nitrate group in complex is not bonded to neodymium,each two neodymium atoms are linked by bridging carboxyl group forming a chain polymeric molecule.展开更多
The spectral parameters of Nd3+ ions in Nd3+:Klu(WO4)2 crystal were calculated based on Judd-Ofelt theory and obtained as follows: for the oscillator strengths ?λ: ?2 = 7.5029×10-20 cm2, ?4 = 7.1837×10-20...The spectral parameters of Nd3+ ions in Nd3+:Klu(WO4)2 crystal were calculated based on Judd-Ofelt theory and obtained as follows: for the oscillator strengths ?λ: ?2 = 7.5029×10-20 cm2, ?4 = 7.1837×10-20 cm2 and ?6 = 3.1189×10-20 cm2; the radiative lifetime is 123 μs; the quantum efficiency is equal to 64.55%; and β1 = 0.5498, β2 = 0.3943, β3 = 0.0551 and β4 = 0.0027 for the fluorescence branch ratios.展开更多
Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designati...Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designation systems. In this paper we presents theoretical calculations using Advanced Dynamics Professional LASCAD software and experimental studies for a high power pigtailed fiber diode laser module of 8 W operating at 808 nm with a specially designed high efficiency cooling system, end pumped high-efficiency Nd:YVO4 laser of 3 × 3 × 10 mm rod and overall cavity length of 44 mm. To the best of our knowledge a self Q-switching effects was generated in Nd:YVO4 laser by changing the cavity dimensions and the position of the intracavity KTP crystal at certain regime of operation for the first time, in which the cavity length is reduced to be 30 mm and the distance between Nd:YVO4 rod and KTP crystal is only 1mm. Self Q-switched laser pulse at 532 nm with high peak power of 96 W, pulse width of 88 ns at FWHM and repetition rate of 400 kHz was achieved. Experimental studies of a passive Q-switched Nd:YVO4 laser using Cr:YAG crystal with three different transmissions of 30%, 40% and 70% were investigated. Passive Q-switched laser pulse at 1064 nm and narrow line width of less than 1.5 nm with highest peak power of nearly 18 kW, short pulse width of less than 4 ns at FWHM and higher repetition rate of 45 kHz using Cr:YAG with transmission of 30% was achieved for the first time.展开更多
文摘The neodymium ions doped gadolinium vanadate (Nd∶GdVO_4) single crystals were successfully grown by Czochralski method. Chemical etching technique was used to reveal the dislocation structure of the crystals. An average dislocation density of (100) plane is 600 pits/mm 2. The crystal-morphology can be used to determine crystal orientation accurately with simple optical method.
基金the National 863 High Technical Program under Grant No.863-715-001-0030.
文摘The thermal lensing effect generated in an end-pumped lightly doped Nd:GdVO4 crystal was found to be considerably weaker than that in Nd:YVO4 having the same Nd3+ concentration. Consequently, the laser performance of Nd:GdVO4 at high pump powers over 20 W was found to be superior to that of Nd:YVO4. TEM00 mode cw radiation of 14.3 W at 1.06μm was achieved with an optical conversion efficiency of 55%, and average slope efficiency of 62%.
文摘Objective:The properties of Nd:GdVO4 laser crystals were studied in application of all-solid laser with LD pumped.Method:We adopted sand wich structural Nd:YVO4 laser crystals experimental devices separately.Results:As to Nd:YVO4 crystal,1.2W continuous laser output at 1064nm was ac-quired with the optical-to-optical transition efficiency of 30%.And as to Nd:GdVO4,1.8W continuous laser out-put at 1064nm was acquired with the optical-to-optical efficiency of 47.2%.Conclusion:All-solid laser is of simple and compact structure,long lifetime,low cost and high efficiency that it will be extensively applied to laser bioengineering,laser environmental monitoring and so on.And comparing the properties of Nd:GdVO4 to that of Nd:YVO4,Nd:GdVO4 would be a more promising all-solid laser crystal.
基金Supported by the Science and Technology Department Project of Jilin Province under Grant Nos 2010PT and 20100355.
文摘A diode-end-pumped electro-optic (EO) Q-switched adhesive-free bond composite Nd:YVO4 laser operating at a repetition rate of 200 kHz is reported.A pair of RbTiOPO4 (RTP) crystals are used as a high repetition EO Q-switch.At the repetition rate of 200kHz,the maximum average output power of 11.8 W at wavelength 1064 nm and full width at half maximum of pulses of 16.65ns are achieved at an incident pump power of 27 W,corresponding to an optical conversion efficiency of 43.7% and a slope efficiency of 44.6%,respectively.To the best of our knowledge,this is the highest repetition rate reported on the EO Q-switched laser by using RTP crystals.
基金Project supported by the National Natured Science Foundation of China （Grant No 60438020）.
文摘The absorption and emission spectra of the YVO4 single crystal co-doped with 1 at.% Nd^3＋ and 1 at.% Yb^3＋ are investigated. The efficient Nd^3＋ → Yb^3＋ energy transfer and the back transfer （Yb^3＋ → Nd^3＋） are observed at room temperature. The fluorescence lifetime of the 4F3/2 level of Nd^3＋ in Nd,Yb：YVO4 is measured under 808 nm laser light excitation. The efficiency of Nd^3＋ → Yb^3＋ energy transfer in YVO4 is determined to be about 34%.
文摘This paper reports the growth, X-ray diffraction and spectroscopy of Nd3＋：Sr3Gd2（BO3）4 crystal. A Nd3＋：Sr3Gd2（BO3）4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3＋：Sr3Gd2（BO3）4 crystal belongs to the orthorhombic system, space group Pnma （D2h） with a = 0.7401, b = 1.604 and c = 0.8755 nm. The absorption and emission spectra of Nd3＋：Sr3Gd2（BO3）4 were investigated. The absorption cross section oa is 3.11 × 10^-20cm2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm. The luminescence lifetime τf is 51.7 μs. The emission cross section oc at 1064 nm wavelength is 1.09 × 10^-19 cm2.
文摘The passively Q-switched and mode-locked（QML） characteristics in a diode-pumped Nd∶GdVO4 laser with Cr4+∶YAG saturable absorbers have been demonstrated. A maximum average output power of 710mW has been obtained in the QML laser. The maximum energy of a single Q-switched pulse is 52.5μJ, with the corresponding pulse width of 30ns and the peak power of 1.75kW, at the incident pump power of 7.75W. The repetition rates of the Q-switched envelope and the mode-locked laser pulse are 16.7kHz and 680MHz, respectively.
文摘Nd:NaBi(WO_4)_2 crystals (Nd:NBW) were grown by Czochralski method. The pulling rate is 0.3 mm·h (-1),and the rotational speed of Nd:NBW crystal is 2 r·min (-1). The components of this single crystal were determined by X-ray diffractions,and its corresponding properties were described from thermal gravity and differential thermal analysis experiments. The absorption cross-sections were calculated. The emission band of Nd:NBW crystal was obtained from its luminous spectrum.
基金supported by the National Natural Science Foundation of China (0041814161)
文摘Synthesis of polycrystalline Nd：Sr0.95Ba0.05WO4 by means of liquid-and solid-phase reaction was reported.X-ray powder diffraction results showed that the as-grown Sr0.95Ba0.05WO4 and Nd：Sr0.95Ba0.05WO4 single crystals belonged to tetragonal system and I41/a space group.Transparent Nd：Sr0.95Ba0.05WO4 single crystal could be obtained along c-axis by Czochralski method from the synthesized polycrys-talline material.As the transmittance of Sr0.95Ba.005WO4 single crystal could reach 80%, Nd3＋ ion was adopted to be doped into the single crystal.Spontaneous Raman spectrums of polycrystalline material and single crystal were measured by RERKZN-ELMER2000 and JY-HR800.By using X-ray fluorescence method, the effective segregation coefficients of Nd, Ba, Sr, and W elements in Sr0.95Ba.005WO4 single crystal were estimated as 0.844（0.745）, 0.44, 1.09, and 0.95, respectively.The segregation coefficients of Nd in Sr0.95Ba0.05WO4 were higher than that in BaWO4, and this is as better as a Raman laser crystal.
文摘The crystal structure of di-hydroxyisobutyrate)diaquo neodymium nitrate Nd(C_4H_7O_3)_2NO_32H_2O was determined by X-ray diffraction analysis. It belongs to monoclinic,space group C2/C,with cell dimensionsa=8.996(1), b=8.601(1),c=21.111(3),β=92.38°,V=1632.O,Z=4,D_c=1.83g/cm^3.Crystal structure has been refined by full-matrix least-square techniques giving a final R value of 0.036.The neodymium atom is coordinated to eight oxygen atoms.The nitrate group in complex is not bonded to neodymium,each two neodymium atoms are linked by bridging carboxyl group forming a chain polymeric molecule.
基金This work was supported by the National Natural Science Foundation of China (50272066) and Key Project of Science and Technology of Fujian Province (2001F004)
文摘The spectral parameters of Nd3+ ions in Nd3+:Klu(WO4)2 crystal were calculated based on Judd-Ofelt theory and obtained as follows: for the oscillator strengths ?λ: ?2 = 7.5029×10-20 cm2, ?4 = 7.1837×10-20 cm2 and ?6 = 3.1189×10-20 cm2; the radiative lifetime is 123 μs; the quantum efficiency is equal to 64.55%; and β1 = 0.5498, β2 = 0.3943, β3 = 0.0551 and β4 = 0.0027 for the fluorescence branch ratios.
文摘Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designation systems. In this paper we presents theoretical calculations using Advanced Dynamics Professional LASCAD software and experimental studies for a high power pigtailed fiber diode laser module of 8 W operating at 808 nm with a specially designed high efficiency cooling system, end pumped high-efficiency Nd:YVO4 laser of 3 × 3 × 10 mm rod and overall cavity length of 44 mm. To the best of our knowledge a self Q-switching effects was generated in Nd:YVO4 laser by changing the cavity dimensions and the position of the intracavity KTP crystal at certain regime of operation for the first time, in which the cavity length is reduced to be 30 mm and the distance between Nd:YVO4 rod and KTP crystal is only 1mm. Self Q-switched laser pulse at 532 nm with high peak power of 96 W, pulse width of 88 ns at FWHM and repetition rate of 400 kHz was achieved. Experimental studies of a passive Q-switched Nd:YVO4 laser using Cr:YAG crystal with three different transmissions of 30%, 40% and 70% were investigated. Passive Q-switched laser pulse at 1064 nm and narrow line width of less than 1.5 nm with highest peak power of nearly 18 kW, short pulse width of less than 4 ns at FWHM and higher repetition rate of 45 kHz using Cr:YAG with transmission of 30% was achieved for the first time.
