Internally folded Nd:YAG and Nd:YVO4 lasers pumped bylaser diodes

An efficient, scalable, diode-pumped Nd laser design is reported. The gain element can be longitudinally pumped along five separate axes and is relatively simple to fabricate. Both Nd:YAG and Nd:YVO₄ gain media were evaluated. Using five single-stripe laser diodes to pump the Nd:YAG, 3.94 W of absorbed power produced 2.1 W CW at 1.06 μm. The slope efficiency was 54 percent and the output was TEM₀₀. The threshold power was 40 mW. No evidence of thermal saturation was observed up to the maximum pump power. Repetitively Q-switched operation is also reported. The maximum output power for Nd:YVO₄ obtained with 2.9 W of pump power was 1.3 W. The slope efficiency was 47 percent     

Efficient upconversion pumping at 1.064 mu m Tm/sup 3+/-doped fluoride fibre laser operating around 1.47 mu m

1.064 mu m upconversion pumping was used to operate a highly efficient CW and Q-switched thulium (Tm/sup 3+/)-doped fluoride fibre laser at around 1.47 mu m. The maximum CW output power was 100 mW for a launched pump power of 570 mW. The threshold power was 200 mW, the slope efficiency 27% and the wavelength width 20 nm. A peak power of 70 W was generated for Q-switching at a launched pump power of 300 mW.<>     

High-power and long-lifetime inGaN blue- violet laser diodes grown by molecular beam epitaxy

InGaN 405 nm multiple quantum well laser diodes grown by molecular beam epitaxy (MBE) with a continuous-wave (CW) lifetime of up to 42 h are reported. The CW threshold current density of the ridge waveguide laser diodes is 3.6 kA/cm² and the slope efficiency for uncoated facets is 0.42 W/A per facet with a maximum CW output power of 45 mW per facet. Statistical variation of CW lifetime with dissipated power is presented for MBE-grown laser diodes from five different wafers.     

Vertical external-cavity surface-emitting laser for dual-wavelength generation

We report an optically pumped vertical external-cavity surface-emitting laser that is designed for emission at two wavelengths simultaneously. Single transverse mode continuous-wave (CW) operation is demonstrated at the wavelengths of 984 and 1042 nm. The device produces a CW optical power of 140 mW for the 984-nm component and 115 mW for the 1042-nm component, exhibiting over 10% efficiency. At a high pump power, self-pulsation of the components appeared on top of the CW-mode components. The maximum total output of 1 W was obtained at the pump power of 9 W.     

半导体可饱和吸收镜调Q的Yb∶LSO激光器

报道了一个激光二极管(LD)抽运多波长连续输出的激光器和一个被动调Q的固体激光器。该激光器的增益材料是一种新型掺Yb3 的晶体Yb3 ∶Lu2SiO5(Yb∶LSO)。当吸收的抽运功率为2.57 W时,连续输出的最大功率为490 mW,斜率效率为22.2%,光-光转换效率为14.2%,激光阈值为299 mW,输出激光波长为1084 nm。多波长输出时,波长调谐范围为1034~1085 nm。利用InGaAs可饱和吸收镜实现调Q输出时,斜率效率为3.0%,激光波长为1058 nm。脉冲重复频率为25~39 kHz,重复频率随着抽运功率的增加而增加。     

A Q-switched diode-pumped neodymium yttrium aluminumborate laser

A report is presented on the first Q-switched laser operation of a room temperature CW diode-pumped Nd:YAB laser. The intense peak fundamental power obtained by Q-switching significantly enhances the green light output from the Nd:YAB laser through the second harmonic conversion process. A peak green power exceeding 3 W was obtained with a CW diode laser input power of 180 mW, as compared to a green output power of only about 1 mW under pure CW operation. Nd:YAB shows considerable promise as a room temperature self-doubling material. Diode-laser-pumped Nd:YAB lasers show promise as compact, and reliable green sources for practical applications     

CW operation of an intracavity pumped molecular submillimeter-wave laser

The 373-μm line of CH3CN was operated in a CW mode in an arrangement where the submillimeter (SMM)-wave laser is placed inside the resonator of the CO2pump laser. 1 mW of CW output power was obtained; this is five times the power of a comparable SMM-wave laser in the common extracavity arrangement. In a pulsed mode, a peak power of 46 mW was measured.     

Tunable CW fibre Raman ring laser centred at 1.41 mu m

The first demonstration of a CW tunable fibre Raman ring laser operating around 1.4 mu m is reported. This laser was pumped by a 3 W Nd:YAG laser operating at 1.319 mu m and tuned over a 10 nm range with a maximum output power of 40 mW.<>     

LD泵浦的Nd:YAG陶瓷激光器

介绍了一种新型的固体激光材料——Nd：Y3Al5O12(Nd：YAG)陶瓷的光学特性,设计并研制成LD泵浦的Nd：YAG陶瓷微型激光器件。阈值泵浦功率为48mW,在泵浦功率为1．5W时获得了516mW的1064nm连续激光输出,光-光转换效率为34．41%。     

Passive Q-switching of an intracavity frequency doubled diode-pumped Nd:YVO/sub 4//KTP green laser with Cr/sup 4+/:YAG

A compact diode-pumped green-pulse laser has been demonstrated by using Cr/sup 4+/:YAG as a saturable absorber in a simple cavity formed by a coated Nd:YVO/sub 4/ crystal and a coated KTP crystal. When continuous-wave (CW) pumped with a fiber-coupled laser diode, the laser produces green pulses of 20-35-ns duration at 532 nm, with a repetition rate of 15-70 kHz. The highest green peak power was 80.8 W, obtained at 1.2 W of pump power, which is 320 times enhancement in comparison to a green output power of 250 mW under CW.     

Low-threshold, high-power, single-longitudinal-mode operation i 1.5μm multiple-quantum-well, distributed-feedback laser diodes

Extremely low-threshold, single-longitudinal-mode operation is reported for 1.5 μm band GaInAs multiple quantum well, distributed feedback laser diodes. A 5.5 mA minimum threshold current as well as 40 mW maximum light output power and 0.33 W/A maximum quantum efficiency have been attained under CW condition at room temperature     

高单脉冲能量被动调Q锁模Tm,Ho: LLF激光器

报道了一种采用氧化石墨烯作为可饱和吸收体的二极管泵浦的被动调Q和调Q锁模运转的Tm, Ho: LLF激光器。采用透过率分别为3%、5%和9%的输出镜,首先研究了Tm, Ho: LLF激光器的连续运转特性。实验和模拟结果均表明采用透过率为9%的输出镜输出特性最好,当最大泵浦功率为20 W时,连续光输出功率高至1793 mW。接着以氧化石墨烯为饱和吸收体,采用透过率为9%的输出镜研究了Tm, Ho: LLF激光器的调Q和调Q锁模特性。实验表明:当790 nm LD泵浦功率小于7.26 W时,激光处于单纯调Q运转状态;当大于7.26 W时,激光器进入稳定的调Q锁模状态,当最大泵浦功率为20 W时,最大输出功率为1052 mW,锁模重复频率为53.19 MHz,对应的平均单脉冲能量为19.77 nJ,该单脉冲能量是目前2 μm锁模激光器的最高指标,同时证实了氧化石墨烯材料在大能量高功率激光锁模中是发展潜力优良的二维锁模材料。     

二极管泵浦Nd:YAG/LBO连续波蓝光激光器

报道了一种半导体二极管(LD)泵浦Nd：YAG晶体，LBO腔内倍频实现了稳定的连续波473hm蓝光激光器，采用简单、结构紧凑的平凹腔设计，当注入功率为17W时，单向获得了234mW的单模蓝光输出。     

Short wavelength (/spl lambda//spl sim/4.3 /spl mu/m) high-performance continuous-wave quantum-cascade lasers

We report continuous-wave (CW) operation of a 4.3-/spl mu/m quantum-cascade laser from 80 K to 313 K. For a high-reflectivity-coated 11-/spl mu/m-wide and 4-mm-long laser, CW output powers of 1.34 W at 80 K and 26 mW at 313 K are achieved. At 298 K, the CW threshold current density of 1.5 kA/cm/sup 2/ is observed with a CW output power of 166 mW and maximum wall-plug efficiency of 1.47%. The CW emission wavelength varies from 4.15 /spl mu/m at 80 K to 4.34 /spl mu/m at 298 K, corresponding to a temperature-tuning rate of 0.87 nm/K. The beam full-width at half-maximum values for the parallel and the perpendicular far-field patterns are 26/spl deg/ and 49/spl deg/ in CW mode, respectively.     

High-temperature(T = 80℃) operation of a 2μm InGaSb-AlGaAsSb quantum well laser

正An InGaSb/AIGaAsSb compressively strained quantum well laser emitting at 2μm has been fabricated. An output power of 82.2 mW was obtained in continuous wave(CW) mode at room temperature.The laser can operate at high temperature(T = 80℃),with a maximum output power of 63.7 mW in CW mode.     

两个激光二极管端面泵浦的基横模Nd：YAG激光器

用两个功率为１．５Ｗ的连续激光二极管偏振耦合端面泵浦及分别从双端同时泵浦Ｎｄ：ＹＡＧ激光器，ＴＥＭ００模ＹＡＧ激光最大输出功率分别为６８０ｍＷ和４９２ｍＷ，总的光－光转换效率分别为２６．４％和１７．７％。从理论上对二极管单端面及双端面泵浦的ＹＡＧ激光器进行了分析计算。     

2.0 W CW, diffraction-limited tapered amplifier with diode injection

The authors have demonstrated an all-semiconductor discrete-element 1.5 mm length tapered-amplifier MOPA (master oscillator power amplifier) emitting up to 2.0 W CW in a diffraction-limited pattern. The tapered single-pass amplifier MOPA exhibits a very high differential efficiency of 72% and a total energy conversion efficiency of 39% at 2.0 W CW output power. The high efficiency of the MOPA is attributed to the tapered amplifier design, which maximises extraction efficiency with a low-power injected beam of 25 mW from a single-mode laser diode. Such an MOPA will have applications where compact, high-efficiency, diffraction-limited sources of radiation are required, such as frequency doubling and free-space communication.<>     

Efficient Nd:YAG slab longitudinally pumped by diode lasers

An efficient scalable 1.06-μm continuous-wave (CW) Nd:YAG slab laser longitudinally pumped by diode lasers is discussed. The 809-nm diode radiation is focused into every laser channel emerging from the reflection points of the 1.06-μm beam on the coated slab surfaces. A maximum CW TEM₀₀ output power of 675 mW has been obtained at a diode pump power of 2 W resulting in a slope efficiency of 40%     

用布氏片实现有效连续和脉冲单频绿光输出

通过对布氏片实现选频的理论分析,采用腔内插入双布氏片和布氏片与Q开关相结合的方法,分别实现了较大功率单频绿光的连续和脉冲稳定输出。在注入抽运功率为1.3W时,连续单频输出平均功率达到124mW,脉冲单频输出峰值功率达到108W。     

二极管激光泵浦的微型绿光调QNd:YVO4激光器

介绍了一种高效率腔内倍频及调QNd:YVO4激光器。激光器的Q开关工作是通过一块腔内KTP晶体实现的,该晶体同时用作倍频晶体,实现类相位匹配。连续工作情况下,在泵浦功率800mW时,得到115mW的绿光输出,光-光转换效率为14.4%。调Q工作时,获得脉宽为5.45ns,峰值功率为74W的脉冲绿光,工作频率为100Hz。