25 research outputs found
Path integral on S2: the rosen-morse oscillator
No full textGuided by the group chain SO(3) 3 0(2), we construct an angular path integral
for the symmetric Rosen-Morse oscillator on S2. By explicit path integration, we obtain
the normalised energy eigenfunction as well as the exact energy spectrumCorresponding Author:
Dr. Mohammad Kayed
Physics Department, College of Science and Humanitarian Studies at Al-Kharj, King Saud University, P.O. Box 83, Al-Kharj, Saudi Arabia 11942. Email: [email protected]
Path integral quantization of the symmetric poschl-teller potential
No full textFeynman's path integral approach to quantum mechanics [I] is expected to be an alternative to Schrodinger's.
Nevertheless, a limited number of problems have been solved exactly by path integration. It is a surprizing fact
that such a typical example as the hydrogen atom has been left unsolved until very recently [2-41. Because of its
gaussian (fresnellian) nature, the functional integral if represented in cartesian variables can be evaluated only for
quadratic potentials [5]. Use of polar coordinates has helped to relax this limitation [6], placing the Infeld-Hull
potential V= ar2 + br-* in the list of path-integable examples. However, the change of variables in path integrals
is not trikial and the result is seldom beneficial to calculations. In recent years, some useful techniques have been
devised, so that coordinate transformations are more effectively utilized to carry out path integration for the
Aharonov-Bohm effect [7], the hydrogen atom [2,3], the Morse oscillator [8], the Dirac-Coulomb problem [4]
and the charge-monopole system [9]. Now we are generally able to evaluate a path integral if it is intrinsically reducible
in the local limit to a confluent hypergeometric equation of the Infeld-Hull type. It is interesting that
this situation is parallel to that of the Sq2.1) dynarnical group approach [lo,) 11.Corresponding Author:
Dr. Mohammad Kayed
Physics Department, College of Science & Humanitarian Studies at Al-Kharj, King Saud University, P.O.Box 83, Al-Kharj 11942, Saudi Arabia. Email: [email protected]
Photoconductivity kinetics in AgIn5S8 thin films
No full textKayed, Tarek S/0000-0003-3482-4166; Ercan, ismail/0000-0001-6490-3792; Qasrawi, Atef/0000-0001-8193-6975WOS: 000283954000034The temperature (T) and illumination intensity (F) effects on the photoconductivity of as grown and heat-treated AgIn5S8 thin films has been investigated. At fixed illumination intensity, in the temperature region of 40-300K, the photocurrent (I-ph) of the films was observed to decrease with decreasing temperature. The I-ph of the as grown sample behaved abnormally in the temperature region of 170-180K. At fixed temperature and variable illumination intensity, the photocurrent of the as grown sample exhibited linear, sublinear and supralinear recombination mechanisms at 300 K and in the regions of 160-260K and 25-130 K. respectively. This behavior is attributed to the exchange of role between the linear recombination at the surface near room temperature and trapping centers in the film which become dominant as temperature decreases. Annealing the sample at 350 K for 1 h improved the characteristic curves of I-ph. The abnormality disappeared and the I-ph - T dependence is systematic. The data analysis of which revealed two recombination centers located at 66 and 16 meV. In addition, the sublinear recombination mechanism disappeared and the heat-treated films exhibited supralinear recombination in most of the studied temperature range. (C) 2010 Elsevier B.V. All rights reserved
Toni Morrison's The Bluest Eye As a Prose Version of T. S. Eliot's The Waste Land
No full textThis paper tries to explain the intertextuality between Toni Morrison's The Bluest Eye and T.S Eliot's The Waste Land. The study discusses characters, settings, allusions, events, and themes in both of these literary works to affirm that The Bluest Eye is a prose version of The Waste Land. While Eliot criticizes the ideology of European people, Morrison criticizes the ideology of White Americans who cause pain and suffering for the Blacks. She highlights African Americans' trauma of oppression, and the spiritual decadence of society. She dramatizes and criticizes the social, cultural and racial injustice that dehumanize Black people. Key Words Toni Morrison; T.S Eliot; Intertextuality; Fragmentation; Rebirth
Microstructural, thermal, and electrical properties of Bi1.7V0.3Sr2Ca2Ca3Ox glass-ceramic superconductor
No full textKayed, Tarek S/0000-0003-3482-4166; Ercan, ismail/0000-0001-6490-3792; Sert, Selin Cavdar/0000-0001-6952-3895; KORALAY, HALUK/0000-0001-7893-344XA glass-ceramic Bi1.7V0.3Sr2Ca2Cu3Ox superconductor was prepared by the melt-quenching method. The compound was characterized by scanning electron microscopy, x-ray diffraction, differential thermal analysis, current-voltage characteristics, transport resistance measurements, and Hall effect measurements. Two main phases (BSCCO 2212 and 2223) were observed in the x-ray data and the values of the lattice parameters quite agree with the known values for 2212 and 2223 phases. The glass transition temperature was found to be 426 degreesC while the activation energy for crystallization of glass has been found to be E-a = 370.5 kJ / mol. This result indicates that the substitution of vanadium increased the activation energy for the BSCCO system. An offset T-c of 80 K was measured and the onset T-c was 100 K. The Hall resistivity rho(H) was found to be almost field-independent at the normal state. A negative Hall coefficient was observed and no sign reversal of rho(H) or RH could be noticed. The mobility and carrier density at different temperatures in the range 140-300 K under different applied magnetic fields up to 1.4 T were also measured and the results are discussed
Heat treatment effects on the structural and electrical properties of thermally deposited AgIn5S8 thin films
No full textThe heat treatment effects on structural and electrical properties of thermally deposited AgIn5S8 thin films have been investigated. By increasing the annealing temperature of the sample from 450 to 500 K, we observed a change in the crystallization direction from (420) to (311). Further annealing of the AgIn5S8 films at 550, 600 and 650 K resulted in larger grain size in the (311) preferred direction. The room temperature electrical resistivity, Hall coefficient and Hall mobility were significantly influenced by higher annealing temperatures. Three impurity levels at 230, 150, and 78 meV were detected for samples annealed at 350 K. The electrical resistivity decreased by four orders of magnitude when the sample annealing temperature was raised from 350 to 450 K. The temperature dependent electrical resistivity and carrier concentration of the thin film samples were studied in the temperature ranges of 25-300 K and 140-300 K, respectively. A degenerate-nondegenerate semiconductor transition at approximately 180 was observed for samples annealed at 450 and 500 K. Similar type of transition was observed at 240 K for samples annealed at 600 and 650 K. (C) 2011 Elsevier Ltd. All rights reserved
Production of Anorthite From Kaolinite and Caco3 Via Colemanite
No full textEuropean Ceramic Society; Turkish Ceramic SocietyBoron oxide has been found to be useful flux for the preparation of dense anorthite ceramics (CaO.Al2O3.2SiO2). Inexpensive starting materials of kaolinite, calcium carbonate and silica were used for anorthite ceramic production. Colemanite (2CaO.3B2O 3.5H2O) was added into the mixtures and the effects of colemanite upon the transformation towards anorthite and on the densification were investigated between 900-1400°C. Single phase anorthite ceramic formed at lower temperatures in boron containing mixtures. Boron containing powder compacts were sintered above 90% theoretical density at 1350°C
