Blue lasers

Interest in AIN, GaN, InN and their alloys for device applications as blue light-emitting diodes and blue lasers has recently opened up new areas of high-pressure synthesis. Near atmospheric pressure, GaN and InN are nnstable with respect to decomposition to the elements far below the temperatures where they might melt. Thus, large boules of these materials typically used to make semiconductor devices caimot be grown from the... 

In additions to improvements in Si, a variety of devices based on compound semiconductors can be expected. Blue lasers witli high brightness and long operating lifetimes already exist in tlie laboratory. LEDs are likely to be used for all lighting purjDoses. The bandwidtli of optical communications will continue to increase witli ever faster semiconductor lasers. 

Fig. 8. A plot of band gap versus lattice constant for Groups 2—16 and 12—16 (II—VI) semiconductors used for the preparation of green and blue lasers.

Nakamura, S. Fasol, G. The blue Laser Diode-, Springer Berlin, 1997. 

AIN, GaN, and InN are attractive materials for applications such as blue lasers and field emitters single-source precursors for these of formula [R2MNR 2]2 (R = alkyl, R = alkyl or H) have been reported.236 The reaction of alkylamines with group 13 trialkyl metal compounds affords oligomeric or polymeric ring and cage structures of metal amides and imides (see section on nitrides). 

Fig. 15.12 The detected emission of various concentrations of fluorescein solutions excited by a 473 nm blue laser using the MCLW chip (arrows indicate the times at which various solutions were added). Reprinted from Ref. 19 with permission. 2008 Elsevier...

Blue-green laser diodes, 22 179 Blue lasers, 22 142... 

The cover of this book shows each of these three processes the stimulated emission represented by the blue light of an Ar+ laser the absorption process responsible for the attenuation of the blue laser in a LiNbOs Pr + crystal and the spontaneous emission that corresponds to the red light emitted from Pr +... 

Figure 5.29 Schematic of GaN based blue laser diode.

Blue lasers allow higher resolution, and hence higher density of optical storage of information, on devices such as DVDs than the infrared GaAs lasers allow. The earliest blue lasers were based on ZnSe but their lifetime proved too short for commercial applications. Lasers based on gallium nitride (GaN), first demonstrated in 1995, have proved to have greater lifetimes. In these lasers, the photons are produced not in a bulk semiconductor but in quantum wells. 

A variety of analytical techniques were then used to verify that Cd(OH)2 was present in the solution when the complex Cd ratio was below the critical value (Re) but absent above it. Cd(OH)2 absorbs in the UV range of the spectrum, and spectral monitoring of Se-free solutions showed that it was present only below Rc. Light scattering by a blue laser also confirmed the presence of a heterogeneous phase below Rc but not above it. Similar XPS analyses to those employed by Rieke and Bentjen for CdS showed that Cd adsorbed on the glass substrate, immersed in Se-free solutions, only below Rc. This is seen in Table 3.1 Appreciable amounts of Cd (as Cd(OH)2) were seen only when the pH was sufficiently high and the complex Cd ratio relatively low. 

Raman spectra of powdered samples in capillary tubes were obtained using a double monochromator spectrometer (Model 1401—Spex Industries, Inc.) with the blue laser line excitation (488 nm). The scattered radiation from the sample was taken at 90° to the incident beam. 

S. Nakamura, G. Fasol [ The Blue Laser Diode (Springer, Germany, 1997) p.79 ]... 

P. Hacke, H. Nakayama, T. Detchprohm, K. Hiramatsu, N. Sawaki [ in Proceedings of the International Symposium on Blue Laser and Light Emitting Diodes (Ohmsha, Tokyo, Japan, 1996) p.184-7]... 

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