Laser stored energy

The term solid-state laser refers to lasers that use solids as their active medium. However, two kinds of materials are required a host crystal and an impurity dopant. The dopant is selected for its ability to form a population inversion. The Nd YAG laser, for example, uses a small number of neodymium ions as a dopant in the solid YAG (yttrium-aluminum-gar-net) crystal. Solid-state lasers are pumped with an outside source such as a flash lamp, arc lamp, or another laser. This energy is then absorbed by the dopant, raising the atoms to an excited state. Solid-state lasers are sought after because the active medium is relatively easy to handle and store. Also, because the wavelength they produce is within the transmission range of glass, they can be used with fiber optics. 

A molecule can store energy in the electronic, vibrational, rotational, and translational degrees of freedom. However, the probability that energy can accumulate in these degrees of freedom and can appear in the form of chemical laser emission differs considerably. Fig. 1 shows the usual form of the reaction profile for an exothermic reaction. It is apparent that a product molecule which has just been released from the activated complex is at some distance from its equilibrium state. It contains excess energy which can in principle be given off in two ways, namely by radiative or collisional processes. There is always competition between these two types of processes. The luminescence quantum yield r]a (4) will be different, depending on the type of excitation. 

To extract the energy stored in NF(a A) in the form of laser power, energy transfer to lasant species such as BiF, NF(i E), IF(5 n), and BH(A n) has been smdied. In a pulsed thermolysis apparatus, BiF(A) concentrations of... 

Energy storage Capability of a doped laser material to store energy as inversion until it is converted to laser light. 

Pumping Process by which the active ions are storing energy in an inversion. The goal is to pump hard enough to drive a laser medium to, or above, the threshold inversion density at which lasing will begin. 

Different lasers use different materials as the active medium. The medium can be either solid, liquid, or gas, and there are advantages for each in the amount of energy that can be stored, ease of handling and storage, secondary safety hazards, cooling properties, and physical characteristics of the laser output. 

WEB A bar code scanner in a grocery store is a He-Ne laser with a wavelength of 633 nm. If 12 kj of energy is given off while the scanner is reading bar codes, how many photons are emitted ... 

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