The retracing behavior of the phase-matching angle(RBPA)in many nonlinear optical crystals for second harmonic generation(SHG)has been demonstrated by calculation.The generality of this phenomenon is successfully expl...The retracing behavior of the phase-matching angle(RBPA)in many nonlinear optical crystals for second harmonic generation(SHG)has been demonstrated by calculation.The generality of this phenomenon is successfully explained by a theoretical analysis based on classical optics.The wavelengths of the fundamental waves and phasematching angles for describing the RBPA of eight kinds of crystals are presented.Furthermore,we point out that RBPA exists generally in both uniaxial and biaxial crystals for both type Ⅰ and type Ⅱ SHG.展开更多
Tunable blue radiation with a tuning range of 340-460nm has been generated using aβ-BaB_(2)O_(4) crystal for external frequency doubling of a ns-pulsed Ti:Al_(2)O_(3) laser.By pumping the Ti:sapphire with 94mJ/pulse ...Tunable blue radiation with a tuning range of 340-460nm has been generated using aβ-BaB_(2)O_(4) crystal for external frequency doubling of a ns-pulsed Ti:Al_(2)O_(3) laser.By pumping the Ti:sapphire with 94mJ/pulse of energy from the second harmonic of a Q-switched Nd:YAG laser,as much as 5.4mJ/pulse at 390nm with a bandwidth of 0.02nm was obtained.This represents an infrared to blue conversion efficiency of 36%and a total conversion(from 532nm to blue)of 5.7%.展开更多
We report the operation of aβ-BaB_(2)O_(4)(BBO)optical parametric oscillator(OPO)broadly tunable in the visible and the near infrared.Quantum efficiency of 22.7%for the signal and 34.1%for the idler corresponding to ...We report the operation of aβ-BaB_(2)O_(4)(BBO)optical parametric oscillator(OPO)broadly tunable in the visible and the near infrared.Quantum efficiency of 22.7%for the signal and 34.1%for the idler corresponding to the total energy conversion efficiency of 25.9%has been achieved.The maximum average output power and the maximum output energy reached 220m W and 22rnJ/pulse,respectively.By changing the matching angle of the OPO,the output wavelength was continuously scanned throughout 425-2144nm.展开更多
A tunable picosecond narrow band β-BaB_(2)O_(4)(BBO)superluminescent optical parametric self-amplification(OPSA)pumped by the third harmonic of an actively-passively mode-locked Nd:YAG laser has been demonstrated.The...A tunable picosecond narrow band β-BaB_(2)O_(4)(BBO)superluminescent optical parametric self-amplification(OPSA)pumped by the third harmonic of an actively-passively mode-locked Nd:YAG laser has been demonstrated.The output wavelength of the OPSA was tunable from 406.6nm to 2777nm.The maximum energy conversion efficiency was 11%.The maximum peak power of the visible output was as high as 13MW.展开更多
High power tunable UV coherent radiation has been achieved by sum-frequency generation(SFG)inβ-BaB_(2)O_(4)(BBO) crystal.The maximum output power obtained is about SMW(near 368nm)and 0.75MW(near 222.5nm)
High power tunable UV laser radiation from 2750Åto 3200 Åhas been obtained by second-harmonic generation in aβ-BaB_(2)O_(4) crystal.A maximum frequency doubling efficiency of 41%and a UV output power of 3.7...High power tunable UV laser radiation from 2750Åto 3200 Åhas been obtained by second-harmonic generation in aβ-BaB_(2)O_(4) crystal.A maximum frequency doubling efficiency of 41%and a UV output power of 3.7MW have been obtained.展开更多
According to the theory of DBR, with the P-type DBR as an example, the electrical characteristics and optical reflection of the DBR are analyzed by studying the energy band structure with various graded region widths ...According to the theory of DBR, with the P-type DBR as an example, the electrical characteristics and optical reflection of the DBR are analyzed by studying the energy band structure with various graded region widths and doping densities. The width and doping density of graded region are decided through a comparative study. The P-type DBR of 980 nm VCSELs is designed with Al0.9Ga0.1As and Al0.1Ga0.9As selected as the high and low refractive index material for the DBR. The 980 nm bottom VCSELs, which consists of 30 pairs P-type DBR and 28 pairs N-type DBR, are then fabricated. In P-type DBR, the width of graded region is 0.02 μm and the uniformity doping concentration is 2.5×10^18cm^-3. Its reflectivity is 99.9%. In N-type DBR, the width of graded region is also 0.02 μm and the uniformity doping concen- tration is 2×10^18cm^-3. Its reflectivity is 99.3%. The I-V curve shows that the series resistance of the device is about 0.05Ω. According to the theory of DBR, with the P-type DBR as an example, the electrical characteristics and optical reflection of the DBR are analyzed by studying the energy band structure with various graded region widths and doping densities. The width and doping density of graded region are decided through a comparative study. The P-type DBR of 980 nm VCSELs is designed, with Al0.9Ga0.1As and Al0.1Ga0.9As selected as the high and low refractive index material for the DBR. The 980 nm bottom VCSELs, which consist of 30 pairs P-type DBR and 28 pairs N-type DBR, are then fabricated. In P-type DBR, the width of graded region is 0.02μm and the uniformity doping concentration is 2.5×10^18cm^-3. Its reflectivity is 99.9%. In N-type DBR, the width of graded region is also 0.02 μm and the uniformity doping concentration is 2×10^18cm^-3. Its refiectivity is 99.3%. The I-V curve shows that the series resistance of the device is about 0.05Ω.展开更多
基金the High Technology Research and Development Programme of China.
文摘The retracing behavior of the phase-matching angle(RBPA)in many nonlinear optical crystals for second harmonic generation(SHG)has been demonstrated by calculation.The generality of this phenomenon is successfully explained by a theoretical analysis based on classical optics.The wavelengths of the fundamental waves and phasematching angles for describing the RBPA of eight kinds of crystals are presented.Furthermore,we point out that RBPA exists generally in both uniaxial and biaxial crystals for both type Ⅰ and type Ⅱ SHG.
基金Supported in part by the Important Programme of Chinese Academy of Sciences。
文摘Tunable blue radiation with a tuning range of 340-460nm has been generated using aβ-BaB_(2)O_(4) crystal for external frequency doubling of a ns-pulsed Ti:Al_(2)O_(3) laser.By pumping the Ti:sapphire with 94mJ/pulse of energy from the second harmonic of a Q-switched Nd:YAG laser,as much as 5.4mJ/pulse at 390nm with a bandwidth of 0.02nm was obtained.This represents an infrared to blue conversion efficiency of 36%and a total conversion(from 532nm to blue)of 5.7%.
基金This work is supported by the Third World Academy of Sciences。
文摘We report the operation of aβ-BaB_(2)O_(4)(BBO)optical parametric oscillator(OPO)broadly tunable in the visible and the near infrared.Quantum efficiency of 22.7%for the signal and 34.1%for the idler corresponding to the total energy conversion efficiency of 25.9%has been achieved.The maximum average output power and the maximum output energy reached 220m W and 22rnJ/pulse,respectively.By changing the matching angle of the OPO,the output wavelength was continuously scanned throughout 425-2144nm.
基金Supported by the Academia Sinica and the Third World Academy of Sciences.
文摘A tunable picosecond narrow band β-BaB_(2)O_(4)(BBO)superluminescent optical parametric self-amplification(OPSA)pumped by the third harmonic of an actively-passively mode-locked Nd:YAG laser has been demonstrated.The output wavelength of the OPSA was tunable from 406.6nm to 2777nm.The maximum energy conversion efficiency was 11%.The maximum peak power of the visible output was as high as 13MW.
文摘High power tunable UV coherent radiation has been achieved by sum-frequency generation(SFG)inβ-BaB_(2)O_(4)(BBO) crystal.The maximum output power obtained is about SMW(near 368nm)and 0.75MW(near 222.5nm)
文摘High power tunable UV laser radiation from 2750Åto 3200 Åhas been obtained by second-harmonic generation in aβ-BaB_(2)O_(4) crystal.A maximum frequency doubling efficiency of 41%and a UV output power of 3.7MW have been obtained.
基金Supported partially by the National Natural Science Foundation of China (Grant Nos. 60636020, 60676034, 60577003, 60706007)
文摘According to the theory of DBR, with the P-type DBR as an example, the electrical characteristics and optical reflection of the DBR are analyzed by studying the energy band structure with various graded region widths and doping densities. The width and doping density of graded region are decided through a comparative study. The P-type DBR of 980 nm VCSELs is designed with Al0.9Ga0.1As and Al0.1Ga0.9As selected as the high and low refractive index material for the DBR. The 980 nm bottom VCSELs, which consists of 30 pairs P-type DBR and 28 pairs N-type DBR, are then fabricated. In P-type DBR, the width of graded region is 0.02 μm and the uniformity doping concentration is 2.5×10^18cm^-3. Its reflectivity is 99.9%. In N-type DBR, the width of graded region is also 0.02 μm and the uniformity doping concen- tration is 2×10^18cm^-3. Its reflectivity is 99.3%. The I-V curve shows that the series resistance of the device is about 0.05Ω. According to the theory of DBR, with the P-type DBR as an example, the electrical characteristics and optical reflection of the DBR are analyzed by studying the energy band structure with various graded region widths and doping densities. The width and doping density of graded region are decided through a comparative study. The P-type DBR of 980 nm VCSELs is designed, with Al0.9Ga0.1As and Al0.1Ga0.9As selected as the high and low refractive index material for the DBR. The 980 nm bottom VCSELs, which consist of 30 pairs P-type DBR and 28 pairs N-type DBR, are then fabricated. In P-type DBR, the width of graded region is 0.02μm and the uniformity doping concentration is 2.5×10^18cm^-3. Its reflectivity is 99.9%. In N-type DBR, the width of graded region is also 0.02 μm and the uniformity doping concentration is 2×10^18cm^-3. Its refiectivity is 99.3%. The I-V curve shows that the series resistance of the device is about 0.05Ω.
