The polarized Raman spectra of deuterated potassium dihydrogen phosphate crystals with different deuterium concentrations are measured.With the increasing deuterium concentration,the Raman peaks which are assigned as ...The polarized Raman spectra of deuterated potassium dihydrogen phosphate crystals with different deuterium concentrations are measured.With the increasing deuterium concentration,the Raman peaks which are assigned as the internal vibrations of the(H/D)_(2)PO_(4)^(-)anion shift to lower wavenumbers.This red-shift contributes to the decrease in the bonding force of the P–O bond as a result of the substitution of deuterium for hydrogen.Moreover,the intensity of the strongest peak of these crystals decreases first,and reaches the minimum value while the mole percentage of the deuterium content in the crystal is about 74%.After that,the intensity increases with the increase of the deuterium concentration in the crystal.展开更多
By using a pulse laser at 532.36 nm as the incident light,stimulated Raman scattering(SRS)of a series of a-cut and c-cut Nd:Lu_(x)Y_(1−x)VO_(4)(x=0,0.10,0.26,0.41,0.61,0.67,0.80)crystals is investigated.For theπ-pola...By using a pulse laser at 532.36 nm as the incident light,stimulated Raman scattering(SRS)of a series of a-cut and c-cut Nd:Lu_(x)Y_(1−x)VO_(4)(x=0,0.10,0.26,0.41,0.61,0.67,0.80)crystals is investigated.For theπ-polarization(E||c),the gain coefficient reduced as x value increased.For theσ-polarization(E||a),the Raman gain of all of the mixed crystals is larger than the pure Nd:YVO_(4),and the maximum value is obtained from the Nd:Lu_(0.1)Y_(0.9)VO_(4)crystal.Such results are also supported by the measurement of spontaneous Raman scattering spectra.展开更多
Effect of pressure on thermal behavior of KDP crystals is investigated by using the in-situ infrared reflective spectra.Compared with that under normal atmosphere,the onset temperature of decomposition under pressure ...Effect of pressure on thermal behavior of KDP crystals is investigated by using the in-situ infrared reflective spectra.Compared with that under normal atmosphere,the onset temperature of decomposition under pressure of 1 MPa is improved to from 210℃to 213℃,suggesting that the thermal stability of KDP is enhanced.Under pressure of 2 MPa,the thermal stability is deteriorated and KDP begins to decompose at 183℃.Under normal atmosphere KDP decomposes in route of translating to K_(4)P_(2)O_(7)firstly,and then to KPO_(3).Under pressures of 1 MPa and 2MPa,KDP translates to KPO_(3)directly without any other polymeric intermediates.展开更多
Low noise image amplification owing to contradirectional two-wave mixing (CTWM) is proposed and demon strafed in Rh-doped BaTiOa crystal. Comparing with the conventional forward two-wave mixing scheme, an enhancement ...Low noise image amplification owing to contradirectional two-wave mixing (CTWM) is proposed and demon strafed in Rh-doped BaTiOa crystal. Comparing with the conventional forward two-wave mixing scheme, an enhancement of signal-to-noise ratio in the order of 103 is obtained. The theoretical analyses are presented and give a reasonable explanation for the experimental results. The further discussion shows that CTWM scheme can also reduce the influence of the crystal absorption and crystal size on the two-wave mixing process to rise the signal beam gain.展开更多
基金Supported by the Program for New Century Excellent Talents in University under Grant No NCET-10-0526the Natural Science Foundation of Shandong Province of China under Grant No ZR2010EM001,the Independent Innovation Foundation of Shandong University under Grant No 2012JC016the Graduate Independent Innovation Foundation of Shandong University under Grant No yzc12073.
文摘The polarized Raman spectra of deuterated potassium dihydrogen phosphate crystals with different deuterium concentrations are measured.With the increasing deuterium concentration,the Raman peaks which are assigned as the internal vibrations of the(H/D)_(2)PO_(4)^(-)anion shift to lower wavenumbers.This red-shift contributes to the decrease in the bonding force of the P–O bond as a result of the substitution of deuterium for hydrogen.Moreover,the intensity of the strongest peak of these crystals decreases first,and reaches the minimum value while the mole percentage of the deuterium content in the crystal is about 74%.After that,the intensity increases with the increase of the deuterium concentration in the crystal.
基金Supported by the National Natural Science Foundation of China(61178060)the Program for New Century Excellent Talents in University(NCET-10-0552)+1 种基金the Natural Science Foundation for Distinguished Young Scholar of Shandong Province(2012JQ18)the Independent Innovation Foundation of Shandong University(2012TS215).
文摘By using a pulse laser at 532.36 nm as the incident light,stimulated Raman scattering(SRS)of a series of a-cut and c-cut Nd:Lu_(x)Y_(1−x)VO_(4)(x=0,0.10,0.26,0.41,0.61,0.67,0.80)crystals is investigated.For theπ-polarization(E||c),the gain coefficient reduced as x value increased.For theσ-polarization(E||a),the Raman gain of all of the mixed crystals is larger than the pure Nd:YVO_(4),and the maximum value is obtained from the Nd:Lu_(0.1)Y_(0.9)VO_(4)crystal.Such results are also supported by the measurement of spontaneous Raman scattering spectra.
基金Supported by the National Natural Science Foundation of China under Grant Nos 50721002 and 50990061.
文摘Effect of pressure on thermal behavior of KDP crystals is investigated by using the in-situ infrared reflective spectra.Compared with that under normal atmosphere,the onset temperature of decomposition under pressure of 1 MPa is improved to from 210℃to 213℃,suggesting that the thermal stability of KDP is enhanced.Under pressure of 2 MPa,the thermal stability is deteriorated and KDP begins to decompose at 183℃.Under normal atmosphere KDP decomposes in route of translating to K_(4)P_(2)O_(7)firstly,and then to KPO_(3).Under pressures of 1 MPa and 2MPa,KDP translates to KPO_(3)directly without any other polymeric intermediates.
基金Supported by a Grant from Key Research Project No.2 in Climbing Program from the State Science of China.
文摘Low noise image amplification owing to contradirectional two-wave mixing (CTWM) is proposed and demon strafed in Rh-doped BaTiOa crystal. Comparing with the conventional forward two-wave mixing scheme, an enhancement of signal-to-noise ratio in the order of 103 is obtained. The theoretical analyses are presented and give a reasonable explanation for the experimental results. The further discussion shows that CTWM scheme can also reduce the influence of the crystal absorption and crystal size on the two-wave mixing process to rise the signal beam gain.
