紫外铜离子激光器的实验研究

采用螺旋形空心阴极放电激励紫外铜离子激光器，实验研究了空心阴极放电，激光增益和激光输出功率特性。     

一次电离的银和铜蒸汽激光器的一瓦运转

本文报导了用一台脉冲运转的空心阴极激光器从800.4、825.5和840.4nmAgⅡ跃迁中获得一W 的多谱线输出功率,从408.6nmAgⅡ跃迁中获得350mW 的输出功率。用一台铜空心阴极激光器从780.8nmCuⅡ跃迁中获得一W 连续输出功率。本文也讨论了空心阴极放电的连续波高功率运转的设计考虑。     

用辐射法研究CuⅡ激光振荡的增益特性

在自制的全金属铜空心阴极激光器中得到了GuⅡ740.4nm(6S~3D_3-5P~3P_2~0)谱线的激光振荡。为研究激光运行的最佳条件,我们用辐射法测量了不同激发条件下GuⅡ740.4nm谱线的增益特性。根据测量的结果,可以得到如下结论:     

三相交流激励的金属蒸汽激光器

本文提供了一种金属蒸汽激光器的新设计,它采用多组电极和三相交流电源激发,对解决空心阴极放电的起弧有较好的作用。观察到铜离子781nm 激光跃迁,并测量了它的特性。     

自终止跃迁机制和R-M激光

众所周知,以铜蒸气激光器为代表的脉冲放电激励的金属蒸气激光器件属于通常的三能级系统,其激光上能级应是与基态有最强光学联系的共振态,而激光下能级则是与基态光学跃迁禁戒的亚稳态,在玻恩近似得以成立的条件下,同一能级的电子碰撞激发速率与自发跃迁速率正关联,因此共振态有可能优于亚稳态被布居形成粒子数反转导致激光．由于激光下能级与基态之间的光学跃迁禁戒,所以激光跃迁将造成其粒子数堆积,激光最终必将自动终止,因此习惯上称作为“自终止跃迁激光器”． 我们完成了包括铜蒸气激光器在内的脉冲放电激励的多种金属蒸气“…     

铜蒸气激光振荡自终止的再认识

铜蒸气激光器是典型的自终止激光器,其激光跃迁通道的下能级是与基态没有光学联系的亚稳态,积累的布居将自动地终止激光。与早先认为主要是激光跃迁本身造就了亚稳态的布居不同,对放电激励的铜蒸气激光器,电子与基态铜原子的碰撞形成对亚稳态的持续激励,电子与激光上能级铜原子的碰撞随着电子温度的降低构成强的消激励作     

紫外铜离子激光器的理论研究

系统研究了连续工作的紫外铜离子激光器理论,即空心阴极放电的阴极位降理论,阴极溅射,放电等离子体中粒子的扩散和粒子数密度的速率方程。计算结果由实验得到验证。     

利用HCD灯测量Gu亚稳态寿命

铜原子能级中存在着两个亚稳态能级(4d~94s~(22)D_(3/2)和4d~94s~(22)D_(5/2)。它们分别是铜蒸气激光器578.2nm和510.6nm激光跃迁的下能级。过去已经在CuCl正柱放电管中测量过这二个亚稳态能级的寿命,在不同的条件下,得到的结果也不尽相同,大致在10到100μs的范围内。利用HCD灯,我们发展了一种新的利用窄脉冲放电激发HCD灯产生Cu亚稳态粒子并在放电结束后测量共振激光感生荧光强度随激光脉冲对放电脉冲延迟时间的衰减关系来测量亚稳态寿命的方法。这里的激光波长共振于下能级为亚稳态的跃迁,即510.6nm:     

空心阴极激光器

一、引言1964年,J.Smith 首次把空心阴极放电用于 He-Ne 混合气体,获得了1.153微米的近红外激光振荡。此后,人们在不同的空心阴极放电中获得了氖-分子气体混合物、纯氖的粒子数反转和激光振荡,以及 CO_2-He 和和 Ar 的空心阴极离子激光器。由于精确理解     

空心阴极脉冲金属离子激光器

众所周知，离子激光器，尤其是金属蒸汽离子激光器，具有大量的辐射波长，光谱复盖自紫外到红外，既可脉冲工作也可连续工作，而且相当经济，这就决定了它们有各种各样的应用。这种激光器激活介质的激励方案之一是把惰性气体和金属蒸汽混合进行空心阴极负辉光放电。这种放电降低了激光器所要求的电源压电，并可用阴极溅射的经济办法把金属蒸汽引入到放电中。此外，如以前所确立的，在空心阴极激光器的等离子体中，由金属原子和缓冲气体离子的电荷交换以及缓冲气体亚稳原子和金属原子的彭宁电离所激起的工作跃迁，其激发效率高于正柱辉光放电。     

The Numerical Simulation Study of Pseudospark Hollow Cathode Discharge

Pseudospark discharges are sources of intense electron beams. Reported in this paper are theoretical studies of the Pseudospark discharges. A theoretical and computational model has been adopted to study the initiation phase of Pseudospark discharges via a two-dimensional electrostatic particle-in-cell plus Monte Carlo (PIC-MCC) collision method. From the numerical results, a sequence of physical events has been identified. It has been found that the ionization processes determined by local electric field and hollow cathode effect. The growth phenomena is dependent of α ionization multiplication due to local space charge from initial ionization growth to onset of the hollow cathode effect, and then hollow cathode effect become leading factor.     

A new DC plasma display panel using microbridge structure andhollow cathode discharge

A newly designed dc plasma display panel (PDP) using a microbridge structure and hollow cathode has been proposed, and its characteristics have been measured. This new plasma display panel operates in an abnormal glow in the current range from 0-50 μA at 500 torr, with an effective internal resistance of 800 KΩ. This means that the internal resistance is high enough that a resistor-in-cell structure is not necessary any more for the dc PDP. The luminous efficiency of the hollow cathode discharge is at least five times as great as that of subnormal and normal glow discharges. The lifetime of the display panel is shown to be quite insensitive to gas pressure in the range of 400-1100 torr because the sputtered materials are trapped inside the hollow cathode     

The characteristics of plasma display with the cylindrical hollowcathode

A newly designed plasma display with a cylindrical hollow cathode has been proposed and investigated to study the relationship between the photoluminous efficiency and the discharge characteristics. The photoluminous efficiency and discharge characteristics are dependent on the geometry factors of the cylindrical hollow cathode and gas pressure in the plasma display. When p×d (where p is the gas pressure and d is the hole diameter of the cylindrical hollow cathode) is below 2 torr·cm, the plasma display has as much as five times higher luminous efficiency compared to that for p×d above 2 torr·cm and it also shows a positive current-voltage (I-V) slope as in an abnormal glow     

Hollow cathode metal ion lasers

A new class of metal ion lasers with significant CW output power in the UV (220-320 nm) and near IR (800-2000 nm) spectral regions is described. In a hollow cathode discharge the upper laser levels are excited via charge transfer collisions between ground state buffer gas ions and ground state metal atoms. At the present stage of development, hollow cathode metal ion lasers are shown to be comparable in UV output power to rare-gas ion lasers but with lower threshold currents by a factor of more than twenty. Visible output powers are lower than rare-gas ion lasers. In the text we present device progress to date, measurements of important plasma parameters, and an outline of potential applications of hollow cathode metal ion lasers.     

1 W operation of singly ionized silver and copper lasers

We report a multiline output power of 1 W from the 800.4, 825.5, and 840.4 nm Ag II transitions and 350 mW from the 408.6 nm Ag II transition resulting from pulsed operation of a silver hollow cathode laser. Continuous output of 1 W was obtained in a copper hollow cathode from the 780.8 nm Cu II transition. Design considerations for continuous high-power operation of the hollow cathode discharge are also discussed.     

冷阴极及其应用

本文介绍了场致发射阴极,次级发射阴极,自热式空心阴极,光电发射阴极的新发展,展示了其广阔的应用前景。     

Kilovolt extraction of dense electron beams from synthesized-plasma cathodes

Electron beams with a continuous current density of 800 A/cm²were extracted from a synthesized-plasma hollow cathode. The beams were accelerated up to potentials of 1.2 kV, through the potential of maximum ionization probability at about 16 volts. There was no accompanying oscillation or gas breakdown. This high voltage operation was made possible by collimating the cesium vapor entering the hollow cathode. The collimation, which was accomplished by use of a narrow slit at the "top" of the cathode, caused the vapor to flow along the cathode wall surface and away from the exit aperture. This minimized escape of neutrals into the high voltage region. The cathode was tested for 200 hours without any signs of degradation. The cathode lifetime is predicted to be several thousand hours at the highest cathode temperature (2425°K) employed in these studies. The extracted 0.030-in diameter beam of 0.250-in length had an electron temperature of less than twice cathode temperature. Longer beams, such as would be used in actual microwave tubes, would require magnetic confinement.     

紫外318.1 nm银离子激光器

A CW and quasi-CW silver ion laser is described operating at 3180 in the UV region by using hollow cathode discharge.     

Three phase excitation of a hollow cathode laser

A new hollow cathode discharge scheme utilizing three phase electrical power at 60 Hz to generate excitation in a sputtered He-Cu laser has been demonstrated. Our results indicate that rectified laser output can be obtained from an unrectified ac power supply using overlapping excitation regions, each excited with a different electric phase. Two preliminary hollow cathode designs are presented, one a tandem and one a transverse configuration. We achieved a rectified or quasi-dc output power of 350 mW. The use of overlapping ac excitation is seen to increase the operating life of a sputtered He-Cu laser and inhibit arc formation in the discharge.     

High-gain ultraviolet Cu-II laser in a segmented hollow cathodedischarge

We report measurements of the discharge and laser characteristics of an ultraviolet (UV) copper ion laser radiating on the 248.6- and 270.3-nm transitions. Our 50-cm active length laser operates in a high-voltage segmented hollow cathode discharge with Brewster windows and external mirrors. The lowest threshold currents were 7.3 and 5.6 A for the above transitions, respectively. The threshold current was found to increase with decreasing active length. We obtained superior gain characteristics (to 11.2 and 8.8%/m gain for the 248.6-and 270.3-nm transitions, respectively, at 0.3 A/cm linear current density) compared with previous studies on UV Cu ion lasers in conventional hollow cathode discharges