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401.
A.D.D. Dwivedi A. Mittal A. Agrawal P. Chakrabarti 《Infrared Physics & Technology》2010,53(4):236-245
In this paper we report an analytical modeling of N+-InP/n0-In0.53Ga0.47As/p+-In0.53Ga0.47As p-i-n photodetector for optical fiber communication. The results obtained on the basis of our model have been compared and contrasted with the simulated results using ATLAS? and experimental results reported by others. The photodetector has been studied in respect of energy band diagram, electric field profile, doping profile, dark current, resistance area-product, quantum efficiency, spectral response, responsivity and detectivity by analytical method using closed form equations and also been simulated by using device simulation software ATLAS? from SILVACO® international. The photodetector exhibits a high quantum efficiency ~90%, responsivity ~1.152–1.2 A/W in the same order as reported experimentally by others, specific detectivity ~5 × 109 cm Hz1/2 W?1at wavelength 1.55–1.65 μm, dark current of the order of 10?11 A at reverse bias of 1.5 V and 10?13–10?12 A near zero bias. These values are comparable to those obtained for practical p-i-n detectors. The estimated noise equivalent power (NEP) is of the order of 2.5 × 10?14 W. 相似文献
402.
The power index formula has been used to obtain the band head spin(I_0) of all the superdeformed(SD) bands in Hg isotopes. A least squares fitting approach is used. The root mean square deviations between the determined and the observed transition energies are calculated by extracting the model parameters using the power index formula. Whenever definite spins are available, the determined and the observed transition energies are in accordance with each other. The computed values of dynamic moment of inertia J~((2)) obtained by using the power index formula and its deviation with the rotational frequency is also studied. Excellent agreement is shown between the calculated and the experimental results for J~((2)) versus the rotational frequency. Hence, the power index formula works very well for all the SD bands in Hg isotopes expect for ~(195)Hg(2, 3, 4). 相似文献
403.
404.
A systematic variation of shape variables \(\beta \) and \(\gamma \) with N and \(N_\mathrm {p}N_\mathrm {n}\) is studied in the framework of an asymmetric rotor model of Davydov and Filippov for the \(Z=\) 50–82, \(N=\) 82–126 major shell space. The role of the \(Z=64\) subshell in producing smooth systematics has been discussed. The quadrupole moments are extracted after considering both axially symmetric and axially asymmetric nuclei. The correlation of \(\beta \) with \(\gamma \) together with the measured quadrupole moments indicates that \(\gamma \)-rigidity is better observed in nuclei with modest deformation. 相似文献
405.
Archiv der Mathematik - The convergence analysis of the Landweber iteration for solving inverse problems in Banach spaces via Hölder stability estimates is well studied by de Hoop et al.... 相似文献
406.
Generalizations of fractional integral inequalities were introduced by many authors. The aim of our investigation is to establish some new fractional integral inequalities using Marichev–Saigo–Maeda (MSM) fractional integral operator for convex function. Further, we obtain some more fractional integral inequalities of Grüss type using MSM operator. 相似文献