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991.
对半导体激光器的P-I特性曲线的非线性引起的三阶载波互调非线性失真进行了理论分析,得出了减少非线性失真的方法,并在实验上获得了验证. 相似文献
992.
993.
994.
WANGJue WANGWei-min 《半导体光子学与技术》2000,6(4):236-241
A novel system configuration of fiber optic sensor based on optical absorption is proposed.Several compensation measures are discussed. A simulated experiment is designed and the output curve of system is given.The experimental result shows that these compensation measures are effective on dynamic disturbances which are caused by background light and optical fiber bend,In addition,the drifts in the light source intensity , fiber losses,and photodetector efficiency are aslo compensated. 相似文献
995.
XIE Wen-Fang 《理论物理通讯》2006,46(6):1101-1104
We study the energy spectra of a two-dimensional two-electron quantum dot
(QD) with Pöschl-Teller confining potential under the influence of
perpendicular homogeneous magnetic field. Calculations are made by using the method of numerical diagonalization of Hamiltonian matrix within the
effective-mass approximation. A ground-state behavior (spin singlet-triplet
transitions) as a function of the strength of a magnetic field is
found. We find that the dot radius R of a Pöschl-Teller potential is
important for the ground-state transition and the feature of ground-state for a Pöschl-Teller QD and a parabolic QD is similar when R is larger. The larger the well depth, the higher the magnetic field for the
singlet-triplet transition of the ground-state of two interacting electrons in a Pöschl-Teller QD. 相似文献
996.
Characteristics of selective oxidation during the fabrication of vertical cavity surface emitting laser 下载免费PDF全文
Taking into account oxidation temperature, N2 carrier gas flow, and the
geometry of the mesa structures this paper investigates the characteristics of
selective oxidation during the fabrication of the vertical cavity surface emitting
laser (VCSEL) in detail.
Results show that the selective oxidation follows a
law which differs from any reported in the literature. Below 435℃
selective oxidation of Al0.98Ga0.02As follows a linear growth law for the
two mesa structures employed in VCSEL. Above 435℃ approximately increasing
parabolic growth is found, which is influenced by the geometry of the mesa
structures. Theoretical analysis on the difference between the two structures for
the initial oxidation has been performed, which demonstrates that the geometry of
the mesa structures does influence on the growth rate of oxide at higher
temperatures. 相似文献
997.
Synthesis and X‐ray powder diffraction studies of semiconducting alloys in the system AgCd2‐xZnxGaS4
O. V. Parasyuk I. D. Olekseyuk O. A. Dzham V. I. Pekhnyo 《Crystal Research and Technology》2006,41(1):32-36
X‐ray powder technique was used in the investigation of AgCd2GaS4–'AgZn2GaS4' section to determine the region of AgCd2GaS4‐based solubility. It was established that the solid solution forms up to 75 mol.% 'AgZn2GaS4'. The refinement of AgCd0.5Zn1.5GaS4 structure was performed. This alloy crystallizes in orthorhombic structure (space group Pmn21 ) with unit cell parameters a =0.78772(2), b =0.67221(2), c =0.64019(2) nm, V =0.33899(3) nm3. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
998.
Metal/semiconductor hybrids consisting of self-assembled CdS nanoparticles on Cd nanowires 下载免费PDF全文
We report on the synthesis and the characterisation of
metal/semiconductor hybrids consisting of self-assembled CdS
nanoparticles on Cd nanowires, which are grown by thermal
evaporation of the mixture of CdS and Cr. The growth of the hybrids
is attributed to the decomposition of CdS at high temperature and
the strain relieving that arises mainly from the lattice mismatch
between Cd and CdS. Temperature dependence of zero-field resistance
of single nanohybrid indicates that the as-produced Cd/CdS
nanohybrid undergoes a metal--semiconductor transition as a natural
consequence of hybrid from metallic Cd and semiconducting CdS. The
metal/semiconductor hybrid property provides a promising basis for
the development of novel nanoelectronic devices. 相似文献
999.
1000.
Improving nucleation in the fabrication of high-quality 3D macro-porous copper film through the surface-modification of a polystyrene colloid-assembled template 下载免费PDF全文
A new approach is developed to the fabrication of high-quality
three-dimensional macro-porous copper films. A highly-ordered
macroporous copper film is successfully produced on a
polystyrene sphere (PS) template that has been modified by
sodium dodecyl sulfate (SDS). It is shown that this procedure
can change a hydrophobic surface of PS template into a
hydrophilic surface. The present study is devoted to the
influence of the electrolyte solution transport on the
nucleation process. It is demonstrated that the permeability of
the electrolyte solution in the nanochannels of the PS template
plays an important role in the chemical electrodeposition of
high-quality macroporous copper film. The permeability is
drastically enhanced in our experiment through the surface
modification of the PS templates. The method could be used to
homogeneously produce a large number of nucleations on a
substrate, which is a key factor for the fabrication of the
high-quality macroporous copper film. 相似文献