First Investigation of Optical Properties and Local Structure of
Gd3+ Doped Nano-Crystalline GeSe2
Issue:
Volume 4, Issue 5, October 2016
Pages:
40-45
Received:
31 October 2016
Accepted:
12 November 2016
Published:
29 November 2016
Abstract: Pure and Gd-doped nano-crystalline GeSe2 were prepared by the melt-quenching technique. The crystal structure, local structure and emission properties are investigated. Structure analysis using Rietveld program suggests monoclinic structure for both virgin and doped samples with nano-particle size 41nm for GeSe2 and 48nm for Gd-doped sample. A wide optical band gap as estimated from absorbance measurements is 4.1ev and 4.8ev for pure and doped samples in accordance with the confinement effects. Raman spectra show two unresolved components at ~ 202 cm-1 with broad line width. Also, well identified low intensity (υ < 145 cm-1) and high intensity (υ > 250 cm-1) bands are detected. For Gd-doped sample, the main band is shifted to lower energies and its FWHM is reduced by ~ 50% accompanied by an intensity increase of about ~ 17 fold times. The photoluminescence analysis of the pure sample shows a main emission band at ~ 604 nm. This band is splitted into two separated bands with higher intensity. The detected emission bands at wavelength > 650 nm are assigned to transmission from 6GJ to the different 6PJ terms.
Abstract: Pure and Gd-doped nano-crystalline GeSe2 were prepared by the melt-quenching technique. The crystal structure, local structure and emission properties are investigated. Structure analysis using Rietveld program suggests monoclinic structure for both virgin and doped samples with nano-particle size 41nm for GeSe2 and 48nm for Gd-doped sample. A wide...
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Behaviour of Non-ideal Saturable Absorber Doped on Active Fiber
Abdallah Ijjeh,
Saed Thuneibat
Issue:
Volume 4, Issue 5, October 2016
Pages:
46-50
Received:
23 September 2016
Accepted:
5 October 2016
Published:
2 December 2016
Abstract: In this paper, a non-ideal saturable absorber doped with an active fiber device is considered. The differential equations that describe the behavior of the device are simplified and solved numerically. The results show that as the non-ideal term (loss) increases, the laser performance degradation increases.
Electrons Break to Photons Even in a Low Voltage Electric Circuit
Issue:
Volume 4, Issue 5, October 2016
Pages:
51-56
Received:
26 October 2016
Accepted:
11 November 2016
Published:
12 December 2016
Abstract: This paper is the theory of breaking electrons in ordinary circuit elements like resistors and Light-Emitting Diodes (LED’s). Undergoing a change of electron has not been considered in the low voltage circuits so far. As it is shown here, there is a difference current before and after LED and resistors. The possibility of leakage current or escaping of electrons from the circuit to make electrostatic charges also considered and tested for LED. It is concluded that the reverse action of Photoelectric effect (eVo=hf-φ), creating energy from mass of electrons are happened not just in a sophisticated high energy accelerators but in daily life electric circuits. Referring to this paper, a large number of missing electrons break to photons, although the drift velocity of electrons is very low. Under going a change of electrons has been considered in the circuits of these experiments. According to the Kirchhoff second rule called the junction rule, the conservation of charge implies the junction rule, because charge does not originate or accumulate or annihilate at this point. It expresses that in any closed single loop electric circuit there is no source or well of charge besides the power supply and the current remains constant at all points of the circuit. Based on the results of this paper and missing some part of current, the conservation of charge does not show high accuracy in this paper.
Abstract: This paper is the theory of breaking electrons in ordinary circuit elements like resistors and Light-Emitting Diodes (LED’s). Undergoing a change of electron has not been considered in the low voltage circuits so far. As it is shown here, there is a difference current before and after LED and resistors. The possibility of leakage current or escapin...
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