Electronic lasers

Laser Stark (or laser electronic resonance) spectroscopy... 

Merger of the ALEE and the IRE in 1963 into the Institution of Electrical and Electronics Engineers (IEEE) preseiwed in its name a sense of the earlier bifurcation of the profession, but in fact the lines had become quite blurred and the numerous constituent societies drew and continue to draw from both traditions. At the end of the centuiy, the IEEE was easily the largest professional organization in the world with membership over 350,000. Its thirty-six constituent societies provided an indication of the degree to which electricity has pervaded the modern world, ranging from Communications and Lasers Electron... 

The overall conceptual layout of the pulsed dye laser LGS system is shown in Fig. 18. A thermally insulated room located on the dome floor houses much of the laser system to minimize vibrations on the telescope and the heat dissipated within the dome. The enclosure houses 6 frequency-doubled Nd YAG pump lasers, the DM0, the associated laser electronics and diagnostics, the... 

Levi, A.F.J., McCall, S.L., Pearton, S.J., and Logan, R.A., 1993, Room temperature operation of submicrometer radius disc laser. Electron. Lett. 29 1666-1667. 

One kind of X-ray lasers is a subcase of the so-called free electron laser. Electrons, accelerated are forced, to almost the speed of light ("relativistic electrons") by klystrons and then bent or wiggled in special magnets called undulators are forced to emit some of their energy as synchrotron radiation inside the undulator, the synchrotron pulses can induce in-phase synchrotron emission by other electrons, thus producing a pulse at X-ray wavelengths. This was recently demonstrated as almost possible (2009). 

Terbium 65 Tb Lasers, electronic materials, erasable optical memory substrate, magnetostrictive alloys... 

Pulse-probe studies using the Laser Electron Accelerator Facility (LEAF) at Brookhaven National Laboratory have revealed changes in optical absorption occurring on the picosecond time scale in rare gas fluids. In xenon, excimers are formed which absorb in the visible and near infra-red as shown in Fig. la. The absorption grows in during the first 50 picoseconds [see Fig. 1(b)].This growth is concomitant with ion recombination that leads first to excited atoms, reaction 1(a), which immediately form excimers, Xe, because of the high density of xenon. 

James R Wishart received a B.S. in Chemistry from the Massachusetts Institute of Technology in 1979 and a Ph.D. in Inorganic Chemistry from Stanford University in 1985 under the direction of Prof Henry Taube. After a postdoctoral appointment at Rutgers University, in 1987 he joined the Brookhaven National Laboratory Chemistry Department as a Staff Scientist in the Radiation Chemistry Group. He founded and presently supervises the BNL Laser-Electron Accelerator Facility for picosecond electron pulse radiolysis. His research interests include ionic liquids, radiation chemistry, electron transfer, and new technology and techniques for pulse radiolysis. He has authored over 90 papers and chapters, and is the co-editor of Advances in Chemistry Series o. 254, Photoehemistry and Radiation Chemistry. 

Moll, H. P. (1994). Electron Paramagnetic Resonance in High Magnetic Field using Far Infrared Lasers Electron Spin Echoes at 604 GHz. Diplomarbeit, Universitat Konstanz. 

Wadsworth, W., Knight, J., Reeves, W. et al., Yb +-doped photonic crystal fibre laser, Electron. Lett., 36, 1452, 2000. 

Verdeyen, Joseph. Laser Electronics. Englewood Cliffs, NJ Prentice Hall, 1994. 

A second method for creating controlled nuclear fusion makes use of a laser beam or a beam of electrons or atoms. In this approach, hydrogen isotopes are suspended at the middle of the machine in tiny hollow glass spheres known as microballoons. The microballoons are then bombarded by the laser, electron, or atomic beam... 

Patterson SG, Petrich SG, Ram RJ, Kolodiejski R (1999) Continuous-wave room temperature operation of bipolar cascade laser. Electron Lett 35 397-397... 

In general there are two lithographic processes used in computer-circuit fabrication -photolithography and radiation (X-ray, laser, electron-beam and deep-UV (248- and 193-nm wavelength)) lithography. The principal difference is the radiation source and wavelength, which in turn define the feature size which can be achieved. 

Laser-electron interaction from classical electrodynamics... 

Both f-f and f-d transitions have been used for lanthanide and actinide lasers. The spectroscopic properties of these transitions are compared in Table I. Since the d states have shorter lifetimes, faster pumping as well as higher energies are required for excitation. Possible pumping sources include ultrafast flashlamps, other lasers, electron beams, or synchrotron radiation, with one exception, all lanthanide and actinide lasers have been optically pumped. 

Determination of the temperature distribution induced by laser, electron, or plasma beam sources is relevant in operations such as surface transformation hardening of metals, drilling, cutting, annealing, shaping, and micromachining. Descriptions of beam-generating devices as well as discussions of applications are available [7-15]. 

Figure 1 Schematic representation of the Laser-Electron Accelerator Facility at Brookhaven National Laboratory. The laser beam is split to generate both the electron pulse and the probe light (scheme courtesy of Dr. J. Wishart, Brookhaven National Laboratory).

To exploit the capabilities of fast lasers, a new picosecond Laser-Electron Accelerator Facility (LEAF) has been recently developed at Brookhaven National Laboratory. In this facility, schematically shown in Figure 1, laser light impinging on a photocathode inside a resonant cavity gun merely 30 cm in length produces the electron pulse. The emitted electrons are accelerated to energies of 9.2 MeV within that gun by a 15 MW pulse of RF power from a 2.9 GHz klystron. The laser pulse is synchronized with the RF power to produce the electron pulse near the peak field gradient (about 1 MeV/cm). Thus the pulse length and intensity are a function of the laser pulse properties, and electron... 

As mentioned above, a 3.5-cell RF photocathode gun is in operation as the accelerator for the Brookhaven National Laboratory Laser-Electron Accelerator Facility. Recently, 1.6-cell RF photocathode guns have replaced thermionic cathode systems as injectors for 30 MeV linear accelerators at Osaka University and the Nuclear Engineering Research Laboratory in Tokai-mura, Japan [6]. Another RF photocathode gun accelerator is under construction at the ELYSE facility at the Universite de Paris-Sud at Orsay, France. A magnesium cathode is in use at LEAF, copper is used at NERL, while the Orsay accelerator will use Cs Te. 

Li, R Sage, J. T. Champion, P. M., Probing picosecond processes with nanosecond lasers Electronic and vibrational relaxation dynamics of heme proteins. /. Chem. Phys. 1992, 97, 3214-3227. 

By crossing the nozzle expansion with some excitation source such as a laser, electron beam or plasma, one might be able to see rotational transitions in excited states. Other types of nozzle sources might allow one to observe combustion or explosion products. Molecular radicals or ions would also be interesting species to study in the large cell by using the pulse techiques described here. 

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