scholarly journals Структура R-=SUB=-1-=/SUB=- и R-=SUB=-2-=/SUB=- полос изотопов иона Cr-=SUP=-3+-=/SUP=- в монокристалле рубина при комнатной температуре

2021 ◽  
Vol 129 (4) ◽  
pp. 494
Author(s):  
В.С. Аракелян ◽  
Т.И. Бутаева ◽  
П.Г. Мужикян ◽  
Д.Г. Заргарян ◽  
Р.Б. Костанян
Keyword(s):  
Stable Isotopes ◽  
Comparative Analysis ◽  
Laser Diode ◽  
Room Temperature ◽  
Selective Excitation ◽  
Luminescence Spectra ◽  
Halogen Lamp ◽  
Combined Structure ◽  
Absorption And Luminescence Spectra ◽  
Excited Luminescence

Abstract. The absorption and luminescence spectra of the R1 and R2 bands in a ruby Al2O3:Cr3+ (0,05%) single crystal at room temperature were studied. The luminescence bands have been obtained both by excitation of the crystal by the radiation of a halogen lamp and by selective excitation of the two upper levels of the 2T1 state using the radiation of a laser diode with a tunable wavelength (656-662 nm). In the spectra of selectively excited luminescence bands, four different displacements of the R1 and R2 bands and four different distances between these bands have been detected, the change of which is a multiple of ~ 0.52 cm-1. A detailed comparative analysis of the obtained spectra of the luminescence bands and their absorption allowed us to determine the combined structure of each of the R1 and R2 bands, formed by additional doublets of these bands of all four stable isotopes of ions 50Cr3+, 52Cr3+, 53Cr3+ and 54Cr3+. The splitting of the obtained doublets varies from 7.04 to 9.14 cm-1 depend on the mass of the isotope

Electronic Spectral Investigations upon the Photochemical Transformations of Some Substituted 1-(N,N-bisacyl)amino-4,5-diphenyl-l,2,3-triazoles

2001 ◽  
Vol 56 (6-7) ◽  
pp. 452-458
Author(s):  
Irina Petkova ◽  
Apostolos J. Maroulis ◽  
Constantina Hadjiantoniou-Maroulis ◽  
Peter Nikolov
Keyword(s):  
Steady State ◽  
Room Temperature ◽  
Uv Light ◽  
Uv Absorption ◽  
Luminescence Spectra ◽  
Model Compounds ◽  
Photochemical Transformations ◽  
Absorption And Luminescence Spectra ◽  
Photochemical Properties ◽  
Substituted 1

Abstract The objective of this report is to investigate the steady state and dynamic photophysical and photochemical properties of 1-(N,N-bisacyl)amino-4,5-diphenyl-1,2,3-triazoles in solvents of dif­ferent polarity at room temperature and in frozen matrix at 77 K. On the basis of the comparison of their UV absorption and luminescence spectra with those of 4,5-diphenyl-1,2,3-triazole and diben-zamide (model compounds), cleavage of the N-N bond in the title compounds after irradiation with polychrome UV light is proved.

Selective Luminescence Spectroscopy of Poly(p-Phenylene) Thin Films at Room Temperature

1995 ◽  
Vol 413 ◽  
Author(s):  
M. A. Drobizhev ◽  
M. N. Sapozhnikov ◽  
V. M. KobryanskII
Keyword(s):  
Thin Films ◽  
Luminescence Spectrum ◽  
Room Temperature ◽  
Selective Excitation ◽  
Luminescence Spectroscopy ◽  
Luminescence Spectra ◽  
Model Calculations ◽  
Localization Threshold ◽  
Low Energy Tail ◽  
Room Temperature Luminescence

ABSTRACTSelectively excited room-temperature luminescence spectra are reported for thin films of poly(p-phenylene) (PPP) deposited onto quartz substrata. The spectra exhibit a localization threshold in the low-energy tail of the luminescence excitation band at vloc.= 22400 cm−1, 2200 cm−1 below the maximum of the excitation spectrum. Upon laser excitation at Vex < Vloc., the maximum Vem of the luminescence spectrum shifts linearly with Vex due to selective excitation of polymer segments. It was found that there exists the frequency range where the slope of the Vem vs Vex dependence is smaller than unity, which corresponds to our previous model calculations for the case of selective excitation of chromophores through broad phonon bands. At vex > vloc,, the luminescence spectrum is independent of Vex. This behavior can be explained if one assumes that upon excitation below the localization threshold the luminescence is related to polymer segments directly excited by laser, whereas upon exciting above the threshold the fast energy relaxation takes place from initially excited states to lower-lying states, from which uminescence occurs.

Activation of Lead Fluoride Room Temperature Luminescence by Structural Modifications

1994 ◽  
Vol 348 ◽  
Author(s):  
D.L. Alov ◽  
A.V. Bazhenov ◽  
V.K. Egorov ◽  
G.A. Emelchenko ◽  
N.V. Klassen ◽  
...  
Keyword(s):  
Room Temperature ◽  
Structural Characteristics ◽  
Structural Defects ◽  
Luminescence Spectra ◽  
Lead Fluoride ◽  
Light Emitting ◽  
X Ray ◽  
Structural Modifications ◽  
Excited Luminescence ◽  
Room Temperature Luminescence

ABSTRACTThe connection of lead fluoride luminescence properties with its structural characteristics has been studied. Single crystals of the cubic and orthorombic phases, cubic and orthorombic powders, pressure compacted orthorombic ceramics, plastically deformed crystals were used. The photo- and X-ray excited luminescence spectra have been investigated. The experimental results have shown that the room temperature luminescence of lead fluoride can be accounted for local light emitting centers which are produced by the intrinsic structural defects in the orthorombic lead fluoride.

Absorption and luminescence spectra of amorphous CdI2 thin films

1999 ◽  
Vol 101-103 ◽  
pp. 299-302 ◽  
Author(s):  
Kazutoshi Fukui ◽  
Kenji Asakura ◽  
Ken-ichi Niimi ◽  
Ikuto Ishizue ◽  
Hideyuki Nakagawa
Keyword(s):  
Thin Films ◽  
Luminescence Spectra ◽  
Absorption And Luminescence Spectra

Tuning the Photophysical Properties of Cyclometalated Ir(III) Complexes by a Trifluoroacetyl Group

2012 ◽  
Vol 67 (3) ◽  
pp. 213-218 ◽  
Author(s):  
Bihai Tong ◽  
Jiayan Qiang ◽  
Qunbo Mei ◽  
Hengshan Wang ◽  
Qianfeng Zhang ◽  
...  
Keyword(s):  
Single Crystal ◽  
Electron Acceptor ◽  
Photophysical Properties ◽  
Red Shift ◽  
Luminescence Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Absorption And Luminescence Spectra ◽  
Homo Lumo

Four cationic Ir(III) complexes, [Ir(dpq)2(bpy)]PF6 (1), [Ir(dpq)2(phen)]PF6 (2), [Ir(tfapq)2- (bpy)]PF6 (3), and [Ir(tfapq)2(phen)]PF6 (4) (dpqH = 2,4-diphenylquinoline, tfapqH = 2-(4ʹ-trifluoroacetylphenyl)- 4-phenylquinoline, bpy = 2,2ʹ-bipyridine, phen = 1,10-phenanthroline) have been synthesized and fully characterized. The structure of 4 was also confirmed by single-crystal X-ray diffraction. The electron-acceptor character of the trifluoroacetyl unit leads to a reduced HOMO-LUMO gap and consequently a red-shift of the UV/Vis absorption and luminescence spectra. The solvophobic character of the trifluoroacetyl unit gives rise to a molecule assembly in solution.

Eu3+ Ion Luminescence Spectra from Lanthanide Sesquioxides Exhibiting Three Different Crystal Structures

1992 ◽  
Vol 46 (2) ◽  
pp. 273-276 ◽  
Author(s):  
G. Chen ◽  
R. G. Haire ◽  
J. R. Peterson
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Room Temperature ◽  
Luminescence Spectra ◽  
Spectral Splitting ◽  
The Eu

We have investigated the Eu3+ ion luminescence spectra from different host crystals of the lanthanide sesquioxides exhibiting either the A, B, or C form. The Eu3+ ion luminescence spectra from B-type Eu2O3 and from Eu3+-doped A-type La2O3 and C-type Lu2O3 were obtained at room temperature. It is suggested that the luminescence from f-f transitions in the Eu3+ ion can be used to determine the crystal structure, because the different Eu3+ ion site symmetries in the different crystal structures give rise to different characteristic spectral splitting patterns.

Photoluminescence of Erbium-Diffused Silicon

1996 ◽  
Vol 422 ◽  
Author(s):  
H. Horiguchi ◽  
T. Kinone ◽  
R. Saito ◽  
T. Kimura ◽  
T. Ikoma
Keyword(s):  
Room Temperature ◽  
Crystalline Silicon ◽  
Luminescence Spectra ◽  
Main Peak ◽  
Silicon Substrates ◽  
Annealing Atmosphere ◽  
Full Width ◽  
Half Maximum ◽  
Strong Luminescence ◽  
Fine Structures

AbstractErbium films are evaporated on crystalline silicon substrates and are thermally diffused into silicon in an Ar+02 or H2 flow. Very sharp Er3+-related luminescence peaks are observed around 1.54 μ m.The main peak as well as the fine structures of the luminescence spectra depend on the annealing atmosphere, suggesting different luminescence centers. The full width at half maximum (FWHM) of the main peaks is ≤ 0.5nm at 20K. Thermal diffusion with Al films on top of the Er films is found to increase the intensity of the Er3+-related peaks greatly. The temperature dependence between 20 K and room temperature is relatively small, and a strong luminescence is obtained at room temperature.

GaN-based blue laser diode with 6.0 W of output power under continuous-wave operation at room temperature

2021 ◽  
Vol 42 (11) ◽  
pp. 112801
Author(s):  
Feng Liang ◽  
Degang Zhao ◽  
Zongshun Liu ◽  
Ping Chen ◽  
Jing Yang ◽  
...  
Keyword(s):  
Laser Diode ◽  
Room Temperature ◽  
Continuous Wave ◽  
Chemical Vapor ◽  
Threshold Current ◽  
Stimulated Emission ◽  
Blue Laser ◽  
Organic Chemical ◽  
Blue Laser Diode ◽  
Continuous Wave Operation

Abstract In this work, we reported the room-temperature continuous-wave operation of 6.0 W GaN-based blue laser diode (LD), and its stimulated emission wavelength is around 442 nm. The GaN-based high power blue LD is grown on a c-plane GaN substrate by metal organic chemical vapor deposition (MOCVD), and the width and length of the ridge waveguide structure are 30 and 1200 μm, respectively. The threshold current is about 400 mA, and corresponding threshold current density is 1.1 kA/cm2.

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