High power infrared lasers

The basic feature of these experiments consists first of producing a metal-cluster-adduct species, as described earlier. Second, a high-power infrared laser is aligned spatially with the cluster beam and fired at a predetermined time so as to intersect the clusters and cluster adducts prior to their arrival at the ionization zone. The effect of the infrared laser is then monitored as a change (loss) in ion signal of the species which have undergone IRMPD. From measurements of depletion as a function of laser frequency and fluence, an infrared dissociation spectrum of the complex is obtained, which can be... 

The drive for developing such lasers was sparked by a very simple observation. If an efficient and scalable visible-ultraviolet laser could be built it would, in principle, be able to produce high intensity radiation in smaller spot sizes at longer distances compared to the then available high power infrared lasers HF,... 

In this section, applications will be discussed which illustrate the versatility and advantages of CVD diamond as an infrared and multi-spectral window material. We describe the use of CVD diamond optical elements including CVD diamond domes and flat plates as windows for IR seekers or imaging systems in high-speed flight or other mechanically aggressive environments. Then we describe the use of CVD diamond windows for the transmission of high-power IR laser beams. 

Shortly after the ruby laser came the first gas laser, developed in 1961 in a mixture of helium and neon gases by A. Javan, W. Bennett, and D. Herriott of Bell Laboratories. At the same laboratories, L. F. Johnson and K. Nassau first demonstrated the now well-known and high-power neodymium laser. This was followed in 1962 by the first semiconductor laser demonstrated by R. Hall at the General Electric Research Laboratories. In 1963, C. K. N. Patel of Bell Laboratories discovered the infrared carbon dioxide laser, which later became one of the most powerful lasers. Later that year A. Bloom and E. Bell of Spectra-Physics discovered the first ion laser, in mercury vapor. This was followed in 1964 by the argon ion laser developed by W. Bridges of Hughes Research... 

Second-harmonic conversion is commonly used with high-power pulsed lasers such as Nd YAG, Nd glass, ruby, or CO2 to generate high-power fixed-frequency radiation at selected wavelengths in the infrared, visible, and ultraviolet. It is also a versatile and convenient source of tunable ultraviolet radiation when the pump radiation is obtained from tunable dye lasers in the visible and near infrared. 

Some of the applications of third- and higher-order frequency conversion are given in Table VII. The th harmonic generation is used to produce radiation at a frequency that is q times the incident frequency. The most commonly used interaction of this type is third-harmonic conversion. It has been used to produce radiation at wavelengths ranging from the infrared to the extreme ultraviolet. Third-harmonic conversion of radiation from high power pulsed lasers such as CO2, Ndiglass, Nd YAG, ruby, and various rare-gas halide and rare-gas excimer lasers has... 

G. Scamarcio et al., High Power Infrared (8-Micrometer Wavelength) Superlattice Lasers, 276,773 (1997). 

The CO2 laser is a near-infrared gas laser capable of very high power and with an efficiency of about 20 per cent. CO2 has three normal modes of vibration Vj, the symmetric stretch, V2, the bending vibration, and V3, the antisymmetric stretch, with symmetry species (t+, ti , and (7+, and fundamental vibration wavenumbers of 1354, 673, and 2396 cm, respectively. Figure 9.16 shows some of the vibrational levels, the numbering of which is explained in footnote 4 of Chapter 4 (page 93), which are involved in the laser action. This occurs principally in the 3q22 transition, at about 10.6 pm, but may also be induced in the 3oli transition, at about 9.6 pm. 

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