Ruby crystal

P.D. Horn and Y.M. Gupta, Luminescence R-Line Spectrum of Ruby Crystals Shocked to 125 kbar along the Crystal c-Axis, Phys. Rev. B 39, 973-979 (1989). 

Other applications of the instrumentation and techniques here presented may include (i) temperature sensing employing alexandrite, ruby crystals, and Nd YAG crystals.(35 41) pH and partial pressure of carbon dioxide (pCCh) may be determined employing carboxy seminaphtorhodafluor (SNARF)-6.(42)... 

Figure 6.8 The Sugano-Tanabe diagram of a 3d electronic configuration (C/5 = 4.5). The two vertical lines correspond to the DqlB values in the crossover and for the ruby crystal (see the text). The inset shows the energy-level diagram for strong crystal fields.

Another important detail on the Sugano-Tanabe diagram shown in Figure 6.8 is the vertical line at the value DqlB = 2.2, at which the states T2g and E are equal in energy. This value of DqlB is usually referred to as the crossover value. Materials (crystal - - ion) for which Dq/B is less than the crossover value are usually called low crystal field materials. Eor these materials, the lowest energy level is the " T2g and so they present a characteristic broad and intense emission band associated with the spin-allowed T2g A2g transition (which is usually a vibronic transition). On the other hand, the materials on the right-hand side of the crossover line are called high crystal field materials. These materials (such as the ruby crystal) present a narrow-line emission related to the spin-forbidden Eg A2g transition, usually called R-line emission. 

In 1960 the first ruby laser was made from a ruby crystal of aluminum oxide (Al Oj). These crystals contain only a small amount of chromium, which stores the energy and is responsible for the laser action. A small amount of chromium found in the mineral corundum is responsible for the bright red color of the ruby gemstone. 

See Fig), because it used a synthetic ruby crystal rod for emission of light (instead of gas used in MASERS). The color of light was red and it was shot in bursts. 

Ruby crystals with a similar texture are found at a contact metasomatic deposit in Myanmar, and are called trapiche rubies. Sapphires with similar textures are also known. Trapiche ruby crystals occur sporadically in marble formed by contact metasomatism due to the intrusion of a granitic magma into Mg-containing limestone. Trapiche sapphire is also formed by the contact metasomatism of Al-rich sedimentary rocks. 

Fig. 7. Experimental arrangement of a giant-pulse laser (Q-switching by dye solution). AM, active material (e.g. ruby crystal rod), F, flashlamp, Mj, 2, resonator mirrors, DC, dye cell...

The first laser produced was the ruby laser. Ruby is a crystal of A1203 in which a fraction of 1 percent of the Al3+ ions is replaced by Cr3+ ions. A diagram of the lowest Cr3+ levels in the ruby crystal is given in Fig. 3.3. The symbols A2, E, T2 are the symmetry-species symbols (Section 1.19). (These are derived using ligand-field theory.) The ruby laser consists of a... 

Pressure calibration is necessary in pressure work, and this is accomplished by incorporating a small ruby crystal with the sample under study. The Ruby scale (4) was developed by the National Bureau of Standards (now the NIST) in 1972, and the sharp Ruby Ri fluorescent line has been calibrated vs. pressure by NIST, and is suitable even up to megabar pressures (5). 

Fig. 33. Polarized emission spectra of single-crystal Ba[Pt(CN)4] 4 H20 at different hydrostatic pressures (T = 295 K)133). The emission intensities at different pressures cannot be compared. The excitation wavelength was varied with pressure to fit approximately the maximum of the E c polarized reflectance. For the high pressure investigations a modified sapphire cell of Bridgman s opposed anvil type was used. The pressure was determined by the amount of red-shift of the Rt- and R2-lines167) of ruby crystals placed around the sample...

C gives ruby crystals.30 It has been used in synthesis of unsolvated perchlorates but can explode on contact with organic matter. 

An Excel spreadsheet illustrating the use of the Solver tool for nonlinear least-squares analysis of a fluorescent decay curve of a ruby crystal. The sum of the squares of residuals is calculated in cell C14 and is minimized in Solver by iterative variation of the parameters in cells CIO, Cll, and C12. 

Solid-State Lasers Radiative Properties of Ruby Crystals Spectroscopic Properties of CdSe Nanocrystals... 

The study of optical centers in solids, liquids, and molecules has fascinated many scientists over a range of years. However, not only scientific curiosity has pushed forward this type of spectroscopy. Simultaneously, many possible applications became clear. The first solid state laser was based on a ruby crystal. Also, in the development of tunable infrared lasers the Cr " " ion played an important role. 

The flame fusion process was the first method to give crystals of acceptable size for commercial applications from the melt, namely ruby crystals for use as gemstones. 

Figure 1. (a) Schematic diagram of crystal growth by the flame fusion method, (b) Stages of development of undoped AI2O3 and Cr-doped (ruby) crystals, (c) Furnace room used for AI2O3 production by H. Djevahirdjian Company at Monthey, Switzerland. (Courtesy of V. Djevahirdjian.)... 

We recently developed a general method, to directly calculate the electronic stracture in many-electron system DV-ME (Discrete Variational MultiElectron) method. The first apphcation of this method has been reported by Ogasawara et al. in ruby crystal (17). They clarified the effects of covalency and trigonal distortion of impurity-state wave functions on the multiplet structure. 

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