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101.
Gang?ChengEmail author Yi?Zhao Jingying?Hou Yu?Duan Yuguang?Ma Shiyong?Liu 《Optical and Quantum Electronics》2004,36(14):1193-1203
In view of their potential applications in flat panel displays, organic light-emitting devices have attracted much attention in the past decade. A challenging target in this field is to realize full color display applications. One of the approaches proposed for these is combining white emission with color filters, where efficient and pure white emission (especially at high brightness) is necessary. In this paper, three kinds of white organic light-emitting devices with different structures and materials are fabricated and their characteristics are discussed. 相似文献
102.
A proton-fuelled DNA nanomachine 总被引:5,自引:0,他引:5
103.
104.
C. Benjamin T. Jonckheere A. Zazunov T. Martin 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(3):279-289
We consider a model for a single molecule with a large frozen spin
sandwiched in between two BCS superconductors at equilibrium, and
show that this system has a π junction behavior at low
temperature. The π shift can be reversed by varying the other
parameters of the system, e.g., temperature or the position of the
quantum dot level, implying a controllable π junction with
novel application as a Josephson current switch. We show that the mechanism
leading to the π shift can be explained simply in terms of the contributions
of the Andreev bound states and of the continuum of states above the superconducting gap.
The free energy for certain configuration of parameters shows a
bistable nature, which is a necessary pre-condition for
achievement of a qubit. 相似文献
105.
H.-K. Zhao Q. Chen 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,55(4):419-427
We have investigated the spectral density of shot noise for the
system of a quantum dot (QD) coupled to two single-wall carbon
nanotube terminals irradiated with a microwave field on the QD. The
terminal features are involved in the shot noise through modifying
the self-energy of QD. The contributions of carbon nanotube
terminals to the shot noise exhibit obvious behaviors. The novel
side peaks are associated with the photon absorption and emission
procedure accompanying the suppression of shot noise. The shot noise
in balanced absorption belongs to sub-Poissonian, and it is
symmetric with respect to the gate voltage. The differential shot
noise displays intimate relation with the nature of carbon nanotubes
and the applied microwave field. It exhibits asymmetric behavior
for the unbalanced absorption case versus gate voltage. The Fano
factor of the system exhibits the deviation of shot noise from the
Schottky formula, and the structures of terminals obviously
contribute to it. The super-Poissonian and sub-Poissonian shot noise
can be achieved in the unbalanced absorption in different regime of
source-drain bias. 相似文献
106.
L. Gao X. P. Yu 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,55(4):403-409
We derive expressions for the effective nonlinear susceptibility
tensors for both the second harmonic generation (SHG) and induced
third harmonic generation (THG) of nonlinear composite materials,
in which nondilute coated particles with radial dielectric
anisotropy are randomly embedded in the linear host. Two types of
coated particles are considered. The first is that the core
possesses a second order nonlinear susceptibility and the shell is
linear and radially anisotropic, while the second is that the
core is linear with radial anisotropy and the shell has a second
order nonlinear susceptibility. We observe greatly enhanced SHG
and THG susceptibilities at several surface plasmon resonant
frequencies. For the second model, due to the coating material
being metallic, there exists two fundamental resonant frequencies
ωc1 and ωc2, whose difference
ωc2-ωc1 is strongly dependent on the interfacial
parameter and the radial dielectric anisotropy. Furthermore, in
both systems, the adjustment of the dielectric anisotropy results
in larger enhancement of both SHG and induced THG susceptibilities
at surface plasmon resonant frequencies than the corresponding
isotropic systems. Therefore, both the core-shell structure and
the dielectric anisotropy play important roles in determining the
nonlinear enhancement and the surface resonant frequencies. 相似文献
107.
In this paper, a new channel drop filter in two dimensional photonic crystals with mirror cavities is proposed. In the structure,
three cavities are used. One is used for a resonant tunneling-based channel drop filter. The others are used to realize reflection
feedback in the bus waveguide, which consists of a point defect micro-cavity side-coupled to a waveguide. The simulation results
by using the finite-difference time-domain method conclude 98% output efficiency. 相似文献
108.
成功研制了测量绝缘体二次电子发射系数的测量装置,该装置主要由栅控电子枪系统、真空系统和电子采集系统组成,测量装置产生的原电子流的能量范围为0.8~60 keV。采用单脉冲电子枪法,测量了原电子能量范围为0.8~45 keV的多晶MgO的二次电子发射系数。测量中,收集极(偏置盒)离材料表面设置为约35 mm,偏置电压设置为 45 V。测量得到:用磁控溅射法制备的MgO的二次电子发射系数最大值约为2.83,处于 2~26范围内,其对应的原电子能量约为980 eV。这表明该装置测量的绝缘体二次电子发射系数是可信的,但用磁控溅射法制备的MgO的二次电子发射系数较低,这可能是制备MgO时引入了过多的杂质在MgO二次电子发射体里面所引起的。 相似文献
109.
110.
投影光刻机硅片调焦调平测量模型 总被引:4,自引:1,他引:4
成像质量是光学光刻机的最主要指标,硅片调焦调平测量是光刻机控制成像质量的基础.为此建立了硅片调焦调平测量系统单个测量点的测量模型,并根据硅片形貌标准和集成电路尺寸标准,推导了近似运算规则,简化了曝光场高度与测量光斑在光电探测器上的位置之间的数学关系.运用最小二乘法和平面拟合曝光场曲面的方法,推导了基于多个测量点的曝光场高度和倾斜测量的数学模型.该模型能满足调焦调平实时测量和控制的需要,可用于测量精度优于10 nm的高精度调焦调平测量系统,能满足线宽小于100 nm投影步进扫描光刻机的需要. 相似文献