Mg:Ru:Fe:LiN-bO3 crystals with various concentrations of MgO (in mole) and fixed content of RuO2 and Fe203 (in mass) are grown with the Czochralski method from the congruent melt. Their infrared transmission sp...Mg:Ru:Fe:LiN-bO3 crystals with various concentrations of MgO (in mole) and fixed content of RuO2 and Fe203 (in mass) are grown with the Czochralski method from the congruent melt. Their infrared transmission spectra are mea- sured and discussed to investigate the defect structure. With the increase of Mg2+ concentration the blue nonvolatile holographic storage capability is enhanced. The nonvolatile holographic storage properties of dual-wavelength recording of Mg(7 mol%):Ru:Fe:LiNbO3 nonvolatile diffraction efficiency, response time, and nonvolatile sensitivity reach 59.8%, 70 s, and 1.04 cm/J, respectively. Comparing Mg(7 mol%):Ru:Fe:LiNbO3 with Ru:Fe:LiNbO3 crystal, the response time is shortened apparently. The nonvolatile diffraction efficiency and sensitivity are raised largely. The mechanism in blue photorefractive nonvolatile holographic storage is discussed.展开更多
The holographic storage properties of Fe (0.03% (mass fraction) Fe2O3):LiNbO3 doped with Sc at different levels (0, 1%, 2%, 3%) were investigated. The Sc threshold concentration in Fe:LiNbO3 was implied to be ...The holographic storage properties of Fe (0.03% (mass fraction) Fe2O3):LiNbO3 doped with Sc at different levels (0, 1%, 2%, 3%) were investigated. The Sc threshold concentration in Fe:LiNbO3 was implied to be about 3% (mole fraction) because O-H vibration absorption peak of Sc (3%):Fe:LiNbO3 was at 3508 cm^-1, compared with 3484 cm^-1 of crystals with lower Sc doping level. Sc(3%):Fe:LiNbO3 exhibited higher optical damage resistance ability. The threshold intensity (wavelength 488 nm) of Sc (3%):Fe:LiNbO3 was 2.2 ×10^2 W ·cm^-2, two orders of masnitude higher than that of Fe:LiNbO3. Holographic storage properties of the crystals were determined in an extraordinary polarized laser of wavelength 632.8 nm by a two-wave coupling method. It was found that in terms of holographic storage properties, the optimal doping concentration of Sc was 2% (mole fraction) among this crystal series.展开更多
In:Fe:Mn:LiNbO3(LN) crystals were grown in air atmosphere by Czochralski method with different concentration of In (0, 1, 2, 3 mol%) in the melts, while the contents of Fe2O3 and MnO were 0.1 and 0.5 mol%, resp...In:Fe:Mn:LiNbO3(LN) crystals were grown in air atmosphere by Czochralski method with different concentration of In (0, 1, 2, 3 mol%) in the melts, while the contents of Fe2O3 and MnO were 0.1 and 0.5 mol%, respectively. The location of doping ions was analyzed by Ultravioletvisible absorption spectra and differential thermal analysis. The diffraction efficiency (η), writing time (τw) and erasure time (τe) of the crystals were measured by two-beam coupling experiment. The dynamic range and photorefractive sensitivity have also been calculated. The results showed that with the increase of In ions in the melt, the absorption edge of In:Fe:Mn:LN crystal shifts to the violet firstly and then makes the Einstein shift, the Curie temperature of crystal increases firstly and then decreases, the storage ratio speeds up, diffraction efficiency decreases, and dynamic range and photorefractive sensitivity increase. The mechanism of holographic storage properties of In:Fe: Mn:LN crystal with different doping concentration of In^3+ was investigated, suggesting the In: Fe:Mn:LN crystals are excellent holographic storage materiel with better synthetical properties than Fe:Mn:LN crystals.展开更多
The congruent tri-doped Mg:Mn:Fe:LiNbO 3 crystal has been grown by Czochralski method. Some crystal samples are reduced in Li 2CO 3 powder at 500 ℃ for 24 hours or oxidized for 10 hours at 1100 ℃ in Nb 2O 5 powder. ...The congruent tri-doped Mg:Mn:Fe:LiNbO 3 crystal has been grown by Czochralski method. Some crystal samples are reduced in Li 2CO 3 powder at 500 ℃ for 24 hours or oxidized for 10 hours at 1100 ℃ in Nb 2O 5 powder. Compared with As-grown Mg:Mn:Fe:LiNbO 3, the absorption edge in UV-Vis. absorption spectrum of the oxidized sample and the reduced shifts to the violet and the red, respectively. Reduction increases the absorption of crystals in visible light region. In two-wave coupling experiments, the writing time, maximum diffraction efficiency and the erasure time of crystal samples in the same conditions are determined. The results indicate that oxidation and reduction disposing has great effect on the holographic recording properties of these crystals. The reduced crystal exhibits the fastest response time of 160 s among the crystal series. The mechanism of post-disposing effect on the holographic recording properties of Mg:Mn:Fe:LiNbO 3 crystals are investigated.展开更多
基金Project supported by the Fundamental Research Funds for the Central Universities of China (Grant No. DL12AB03)the National Natural Science Founda-tion of China (Grant No. 60777006)
文摘Mg:Ru:Fe:LiN-bO3 crystals with various concentrations of MgO (in mole) and fixed content of RuO2 and Fe203 (in mass) are grown with the Czochralski method from the congruent melt. Their infrared transmission spectra are mea- sured and discussed to investigate the defect structure. With the increase of Mg2+ concentration the blue nonvolatile holographic storage capability is enhanced. The nonvolatile holographic storage properties of dual-wavelength recording of Mg(7 mol%):Ru:Fe:LiNbO3 nonvolatile diffraction efficiency, response time, and nonvolatile sensitivity reach 59.8%, 70 s, and 1.04 cm/J, respectively. Comparing Mg(7 mol%):Ru:Fe:LiNbO3 with Ru:Fe:LiNbO3 crystal, the response time is shortened apparently. The nonvolatile diffraction efficiency and sensitivity are raised largely. The mechanism in blue photorefractive nonvolatile holographic storage is discussed.
基金Project supported by Natural Science Foundation of Heilongjiang Province (E200512)
文摘The holographic storage properties of Fe (0.03% (mass fraction) Fe2O3):LiNbO3 doped with Sc at different levels (0, 1%, 2%, 3%) were investigated. The Sc threshold concentration in Fe:LiNbO3 was implied to be about 3% (mole fraction) because O-H vibration absorption peak of Sc (3%):Fe:LiNbO3 was at 3508 cm^-1, compared with 3484 cm^-1 of crystals with lower Sc doping level. Sc(3%):Fe:LiNbO3 exhibited higher optical damage resistance ability. The threshold intensity (wavelength 488 nm) of Sc (3%):Fe:LiNbO3 was 2.2 ×10^2 W ·cm^-2, two orders of masnitude higher than that of Fe:LiNbO3. Holographic storage properties of the crystals were determined in an extraordinary polarized laser of wavelength 632.8 nm by a two-wave coupling method. It was found that in terms of holographic storage properties, the optimal doping concentration of Sc was 2% (mole fraction) among this crystal series.
基金Harbin Science and Technology Project (No. 2005AA5CG058)Natural Science Foundation of Heilongjiang Province (No. A0203)
文摘In:Fe:Mn:LiNbO3(LN) crystals were grown in air atmosphere by Czochralski method with different concentration of In (0, 1, 2, 3 mol%) in the melts, while the contents of Fe2O3 and MnO were 0.1 and 0.5 mol%, respectively. The location of doping ions was analyzed by Ultravioletvisible absorption spectra and differential thermal analysis. The diffraction efficiency (η), writing time (τw) and erasure time (τe) of the crystals were measured by two-beam coupling experiment. The dynamic range and photorefractive sensitivity have also been calculated. The results showed that with the increase of In ions in the melt, the absorption edge of In:Fe:Mn:LN crystal shifts to the violet firstly and then makes the Einstein shift, the Curie temperature of crystal increases firstly and then decreases, the storage ratio speeds up, diffraction efficiency decreases, and dynamic range and photorefractive sensitivity increase. The mechanism of holographic storage properties of In:Fe: Mn:LN crystal with different doping concentration of In^3+ was investigated, suggesting the In: Fe:Mn:LN crystals are excellent holographic storage materiel with better synthetical properties than Fe:Mn:LN crystals.
基金The subject has been supported by Chinese National Advanced Technology 863 Project(Grant No.8632001AA31304)Chinese National 973 Project(Grant No.G19990330).
文摘The congruent tri-doped Mg:Mn:Fe:LiNbO 3 crystal has been grown by Czochralski method. Some crystal samples are reduced in Li 2CO 3 powder at 500 ℃ for 24 hours or oxidized for 10 hours at 1100 ℃ in Nb 2O 5 powder. Compared with As-grown Mg:Mn:Fe:LiNbO 3, the absorption edge in UV-Vis. absorption spectrum of the oxidized sample and the reduced shifts to the violet and the red, respectively. Reduction increases the absorption of crystals in visible light region. In two-wave coupling experiments, the writing time, maximum diffraction efficiency and the erasure time of crystal samples in the same conditions are determined. The results indicate that oxidation and reduction disposing has great effect on the holographic recording properties of these crystals. The reduced crystal exhibits the fastest response time of 160 s among the crystal series. The mechanism of post-disposing effect on the holographic recording properties of Mg:Mn:Fe:LiNbO 3 crystals are investigated.