With the development of the diode laser pump sources,the Yb 3+ doped crystals have brought much attention which is not suitable for flash light pump source since they are not match in spectrum region.Comparing with Nd...With the development of the diode laser pump sources,the Yb 3+ doped crystals have brought much attention which is not suitable for flash light pump source since they are not match in spectrum region.Comparing with Nd 3+ doped crystals,Yb 3+ doped crystals have many advantages,for example, (1)Yb 3+ doped crystals have very low thermal load,(only about 1/3 of that of Nd 3+ doped crystals) therefore,the systems can obtain lasers with higher optical quality and higher average power. (2)The energy stored up ability of Yb 3+ doped crystals is about 5 times as much as that of Nd 3+ doped crystals. (3)The position of main absorption peak of Yb 3+ matches to the pumping InGaAs diode emission,which is more durable than the AlGaAs diode used to pump the Nd 3+ . (4)The full width at half maximum of Yb 3+ doped crystals is 10 times as much as that of Nd 3+ doped crystals,so,the temperature control requirement of laser diode is relatively moderate. (5)From the point of view of energy transfer,because of the inherently small quantum defect of the Yb 3+ ,the theoredtical quantum efficiency can get up to 91%.展开更多
The optical quality of Er^3＋, yb^3＋： BaWO4 crystal was gown by Czochralski method. Absorption spectra were measured and energy levels were assigned. According to Judd-Ofelt theory, the spectral strength parameters ...The optical quality of Er^3＋, yb^3＋： BaWO4 crystal was gown by Czochralski method. Absorption spectra were measured and energy levels were assigned. According to Judd-Ofelt theory, the spectral strength parameters of Er^3＋ ion were fitted to beΩ2 =0.3926 x 10^-20 cm^2, Ω4 =0.0721×10^-20 cm^2, Ω6 =0.0028 ×10.20 cm^2. Emission peaks centered at around 523,544 and 670 nm were observed under 334 nm He-Cd laser excitation and emission peaks centered at 1001 and 1534 nm were detected under 976 nm laser excitation. Strong green emission was also observed when the crystal was pumped with 808 nm and 976 nm laser. The mechanisms of frequency upconversion and sensitization were analyzed.展开更多
Growth and morphology of neodymium or ytterbium doped calcium gadolinium yttrium oxoborate (Re∶Ca 4Gd x Y 1- x O(BO 3) 3(Re∶GdYCOB)Re =Nd,Yb; x =0-1)were systematically studied. Polycrystalline materials used for Re...Growth and morphology of neodymium or ytterbium doped calcium gadolinium yttrium oxoborate (Re∶Ca 4Gd x Y 1- x O(BO 3) 3(Re∶GdYCOB)Re =Nd,Yb; x =0-1)were systematically studied. Polycrystalline materials used for Re∶GdYCOB single crystals growth were synthesized by multistage solid phase reaction method.Re∶GdYCOB single crystals were grown by Czochralski technique.The pulling rates are 0.5-2mm/h and the rotation rates are 10-30r/min.Usually 65-75% polycrystalline materials can be transformed into good quality single crystals under our growth conditions. The structures of some as grown Re∶GdYCOB single crystals were measured by using a four circle diffractometer.The results measured show that the space group of the crystals is C 3 s Cm.The determined lattice constants of 8 at% Nd doped Ca 4YO(BO 3) 3 single crystal are a =0.8076nm, b =1.6020nm, c =0.3527nm , β =101.23°.展开更多
文摘With the development of the diode laser pump sources,the Yb 3+ doped crystals have brought much attention which is not suitable for flash light pump source since they are not match in spectrum region.Comparing with Nd 3+ doped crystals,Yb 3+ doped crystals have many advantages,for example, (1)Yb 3+ doped crystals have very low thermal load,(only about 1/3 of that of Nd 3+ doped crystals) therefore,the systems can obtain lasers with higher optical quality and higher average power. (2)The energy stored up ability of Yb 3+ doped crystals is about 5 times as much as that of Nd 3+ doped crystals. (3)The position of main absorption peak of Yb 3+ matches to the pumping InGaAs diode emission,which is more durable than the AlGaAs diode used to pump the Nd 3+ . (4)The full width at half maximum of Yb 3+ doped crystals is 10 times as much as that of Nd 3+ doped crystals,so,the temperature control requirement of laser diode is relatively moderate. (5)From the point of view of energy transfer,because of the inherently small quantum defect of the Yb 3+ ,the theoredtical quantum efficiency can get up to 91%.
基金Project supported by the Key Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences
文摘The optical quality of Er^3＋, yb^3＋： BaWO4 crystal was gown by Czochralski method. Absorption spectra were measured and energy levels were assigned. According to Judd-Ofelt theory, the spectral strength parameters of Er^3＋ ion were fitted to beΩ2 =0.3926 x 10^-20 cm^2, Ω4 =0.0721×10^-20 cm^2, Ω6 =0.0028 ×10.20 cm^2. Emission peaks centered at around 523,544 and 670 nm were observed under 334 nm He-Cd laser excitation and emission peaks centered at 1001 and 1534 nm were detected under 976 nm laser excitation. Strong green emission was also observed when the crystal was pumped with 808 nm and 976 nm laser. The mechanisms of frequency upconversion and sensitization were analyzed.
文摘Growth and morphology of neodymium or ytterbium doped calcium gadolinium yttrium oxoborate (Re∶Ca 4Gd x Y 1- x O(BO 3) 3(Re∶GdYCOB)Re =Nd,Yb; x =0-1)were systematically studied. Polycrystalline materials used for Re∶GdYCOB single crystals growth were synthesized by multistage solid phase reaction method.Re∶GdYCOB single crystals were grown by Czochralski technique.The pulling rates are 0.5-2mm/h and the rotation rates are 10-30r/min.Usually 65-75% polycrystalline materials can be transformed into good quality single crystals under our growth conditions. The structures of some as grown Re∶GdYCOB single crystals were measured by using a four circle diffractometer.The results measured show that the space group of the crystals is C 3 s Cm.The determined lattice constants of 8 at% Nd doped Ca 4YO(BO 3) 3 single crystal are a =0.8076nm, b =1.6020nm, c =0.3527nm , β =101.23°.
