A miniature electron beam pumped laser

The 1.73 μm XeI laser has been operated in a fully continuous mode using a table-top electron beam pumped laser setup. A 12 keV electron beam sent through a 300 nm thick silicon nitride membrane into a laser gas mixture of typically 600 mbar gas pressure was used for pumping. A low loss cavity was installed, resulting in a very low pumping power of 37 mW to reach laser threshold. The geometrical conditions for the laser setup such as the shape of the beam pumped volume and its overlap with the optical mode volume are discussed. The laser scheme has been clearly identified as a recombination laser scheme by operating the laser in pulsed mode and observing the time structure of the laser pulse.     

Time delay in CdS laser pumped by an electron beam

Time delays of up to 500 nsec were observed in the stimulated emission of Cd-rich CdS crystals at 80° K pumped by an electron beam. The delay decreased with increase of excitation and the memory effect of the first pulse was observed for lasing during the second pulse when two separated electron-beam pulses (double pulse) were applied to the sample.The results were compared with the trapping model proposed by Fenner in which traps provide a large amount of optical absorption and the expression for the delay in the case of electron-beam pumping was derived. The experimental results were well explained by this model.     

Pulsed power for a rep-rate, electron beam pumped KrF laser

A new type of pulsed power system has been designed and built for a rep-rate, electron beam, pumped KrF laser. The system consists of two independent 11.2-kJ generators, which operate continuously at 5 Hz and produce two opposing 500-kV, 110-kA, 100-ns flat-top electron beams. The system combines the spark gap prime switch/step-up transformer design from the AIRIX and DAHRT injectors, and the water pulse-forming lines/output switch/vacuum insulator design from the Nike 60-cm amplifier. The system is fully operational, with both sides operating together. One side has operated continuously at 5 Hz for 90000 shots. The paper describes the system and the results of initial tests, including electrode wear     

Color center laser pumped by a flashlamp-pumped dye laser

A reliable, pulsed, color center laser is described which provides a pulse energy up to 0.4 mJ in a wavelength range from 2.4 μm to 3.3 μm at a bandwidth below 20 GHz. A simple, broadband, flashlamp-pumped dye laser is used as the pump source. A new transverse pumping scheme of F-centers is described using hydrogenated color center crystal which allows to pump color center lasers with high energy pump pulses.     

Continuous wave dye laser pumped by a HeNe laser

Continuous wave operation of a dye laser pumped at 633 nm by a HeNe laser is reported. A jet of a cooled solution of Oxazine 1 in ethanol was used as the laser medium in an asymmetric spherical cavity. With mirrors of high reflectivity a threshold as low as 10 mW could be achieved.     

Modeling a distributed feedback dye laser pumped by a Nd-glass laser

A mathematical model has been developed to describe the dynamic emission of a distributed feedback dye laser (DFDL) pumped by a Nd-glass laser. The model is based on the coupled-wave theory. It allows the investigation of the temporal behavior of the Nd-glass pumping laser source and the DFDL pulses. The model allows studying the effect of the variation of the laser input parameters of the Nd-glass laser, such as maximum amplification coefficient, loss coefficient and pumping rate on the characteristics of DFDL pulses regarding the pulse width, delay time and separation time. The feedback process of the DFDL is provided either by changes of the refractive index or by optical gain or by both together. The model estimates the following: temporal behavior of the density of emitted radiation, energy densities of the first excited singlet and triplet states, DFDL output power, cavity decay time and the temperature of the produced grating. The numerical solution of the nonlinear coupled rate equation system predicts the generation of DFDL picosecond pulses. The calculated results are in good agreement with the available experimental data. The calculations were done using rhodamine 6G dissolved in ethanol as the investigated matrix.     

Fiber Raman laser pumped by a Nd:YAG laser

We have pumped a fiber Raman laser with a cw mode-locked Nd:YAG laser operating at 1319 nm and generated pulses as short as 160 fsec using soliton pulse shaping in the fiber. We have also constructed a completely integrated oscillator loop using a fiber optic coupler and fusion splicing.     

Free electron laser spectral dynamics with a modulation of electron beam energy

Recent experimental and theoretical works on free electron laser spectral dynamics have pointed out the difficulty to obtain a narrow and stable spectrum operation. This goal can only be achieved by avoiding the sideband generation leading to a broadband and unstable spectrum. Tapered wiggler and two-frequency wiggler are well suited for combining sharp spectrum and high efficiency but are not really compatible with a wide tunability of laser light. Filtering sidebands is a good way for lower power experiments but it seems to be difficult to conceive wideband filters, specially in the far-infrared region. Modulation of electron energy is a new potential soft way for controlling the spectral dynamics of longpulse free electron laser. Spectral dynamics under the modulation is investigated in the linear and non-linear regimes in the far-infrared region. Simulations show that a pulsed and sharp spectrum behavior can be obtained by optimizing the modulation parameters. The interest of such a method for the far-infrared experiments is discussed.     

A subpicosecond dye laser pumped by a xenon ion laser

A pulsed xenon ion laser has been used to pump a rhodamine 6G dye laser utilizing a ring resonator. The dye laser has been passively mode-locked; a pulsewidth of 0.5 ps and a 50 kW peak power have been obtained.Work partly supported by Italian C.N.R.     

A mode-locked dye laser pumped by a xenon ion laser

Passive mode-locking of a rhodamine 6G dye laser has been achieved, using a pulsed xenon ion laser as a pumping source. A pulse width of 5 ps and a peak power of 4 kW have been obtained. Thermal problems were encountered, which adversely affected the operation of the dye laser. Work is in progress to improve these results.     

Free-running emerald laser pumped by laser diode

Free-running emerald laser pumped by 660-nm laser diode (LD) was reported. Free-running output powerof 24 mW has been obtained with overall efficiency of 1.4% and slope efficiency of 11.9% when the LD incident power was 2.56 W. The laser threshold value of emerald crystal was estimated to be 0.7 W.     

同带泵浦高功率超荧光光源

报道了一台基于同带泵浦技术的主振荡功率放大(MOPA)结构超荧光光纤光源。首先利用自行搭建的超荧光种子源获得了半高全宽(FWHM)线宽10.3 nm的宽谱超荧光种子,经光谱滤波得到FWHM线宽1.8 nm的窄谱种子光;种子光经二级预放大器放大至104.4 W后注入主放大器;主放大器最高输出功率3.14 kW,最高输出功率时光光转换效率80.74%,光谱FWHM线宽4.68 nm,光束质量因子为1.59。进一步提高系统泵浦功率有望获得更高功率输出。     

Power output coupling in a dye laser pumped by a nitrogen laser

A simple model for the operation of a pulsed dye laser, transversely pumped by a nitrogen laser, is presented. We consider the combined effect of the transmission of the laser output coupler, its distance from the dye cell and the saturated gain characteristics of the dye laser medium, on the operation of the laser. Experimental results are interpreted in terms of this model.     

A free-electron laser pumped by the soliton laser

We propose a scheme for building a free-electron laser in the soft X-ray region pumped by the soliton laser. Making use of soliton laser wave evolution shape and single-pass small signal analysis, we find that this laser has two special advantages over the previous electromagnetic wave undulator free-electron lasers. One is a very small mass-shift effect because of the special characteristics of soliton laser; the other is that it has an additional frequency tuning effect based on the conventional free-electron laser's tunability. We also obtain the small signal gain and present some discussion.     

利用皮秒脉冲激光驱动瞬态X射线激光

报道了利用皮秒激光驱动产生瞬态类镍银X射线激光的实验结果.采用一路脉冲宽度为数百皮秒的激光作为预脉冲，配合另一路皮秒激光作为主脉冲联合驱动平面靶，获得了一定强度的类镍银X射线激光输出，输出能量约为5—10nJ. 关键词： 瞬态X射线激光 长短脉冲联合驱动 皮秒脉冲激光     

Flash-lamp pumped dye laser excited by a transverse discharge

A flash-lamp pumped dye laser has been described in which the discharge responsible for the working medium excitation was transverse to the capillary filled with the dye. It was shown that such arrangement allows for the lamp operation at the atmospheric pressure and makes possible generation of short pulses of light.