共查询到20条相似文献,搜索用时 15 毫秒
1.
Anton A. Akhsakhalyan Aram D. Akhsakhlyan Alexander I. Kharitonov Eugenie B. Kluenkov Vladimir A. Murav’ev Nikolay N. Salashchenko 《Central European Journal of Physics》2005,3(2):163-177
This paper is an overview of the research activities carried out in the past five years at the Institute for Physics of Microstructures
RAS and “X-ray” Company towards the manufacture of multilayer mirror systems capable of forming X-ray beams in the subnanometer
range of wavelengths. The systems fabrication technology is presented, including techniques for producing supersmooth surfaces
of specified shape, methods of graded multilayer structure deposition on such surfaces, and the principles of designing optimal
mirror parameters. The characteristics of a quadrelliptical reflector—a novel high light-gathering power four-corner focusing
system—are reported. 相似文献
2.
A. A. Akhsakhalyan A. D. Akhsakhalyan Yu. A. Vainer M. V. Zorina E. B. Klyuenkov V. A. Murav’ev N. N. Salashchenko A. I. Kharitonov 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(1):38-40
We review the recent studies and results obtained in the last five years at the Institute for Physics of Microstructures (IPM)
in the field of multilayer mirror construction for hard X-ray wavelength range ( 7n = 0.05—0.25 nm), E = 25—5 keV)). Mirrors with cylindrical and spheroidal shapes as well as Kirkpatrick-Baez cross systems are considered. 相似文献
3.
Considering light interference in an octonion formalism, it is shown that the interference equations in nonassociative theory
obtained in [1] have an octonion solution. The associator — a new characteristic of the interference field — is a qualitative
measure of the memory of the medium.
Tbilisi Medical University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 54–60, August, 1996. 相似文献
4.
5.
To improve light extraction from organic electroluminescent (EL) devices, we introduced a diffusive substrate with 25 μm thickness
consisting of high refractive index resin and scattering particles. It is expected that the diffusive substrate with high
refractive index matrix converts the waveguided emission into external emission from both glass substrate and indium-tin-oxide/organic
layer. We used the ray tracing method to optimize the scattering effect and to verify the coupling out effect of the diffusive
high refractive index substrate. With the use of the ray tracing calculation, an increase in the external emission up to a
factor of 2.7 was expected compared to use of a common glass substrate. Experimentally, the coupling out effect of the diffusive
high refractive index substrate strongly depended on the thickness of electron transporting layer (ETL) due to the well-known
interference effect. The current efficiency increased by a factor of 1.3 for an organic EL device with a 60-nm-thick ETL and
by a factor of 6.8 for one with a 120-nm-thick ETL. 相似文献
6.
V. Vaicikauskas R. Antanavicius R. Januskevicius 《International Journal of Infrared and Millimeter Waves》1997,18(2):383-389
ATR prism was used firstly as the FIR laser output coupler. Such output mirror possesses good separation of the pump (λ≈10μm)
and FIR radiation without losses. Transmittance of this mirror can be simply controlled by adjustment of gap between two output
prisms. The dependence of mirror output characteristics on pump radiation polarization, prism refractive index, gap between
prisms are under consideration. 相似文献
7.
A near-field scanning optical microscope (NSOM), which we built, is used to investigate 1–5-μm wide stripes with a 10-nm thick
layer—a quantum well — on a GaAs surface. A map of the photoluminescence intensity is obtained synchronously with the topographic
profile of the structures. The measured spatial distribution of the photoluminescence intensity is described satisfactorily
in a model that takes into account carrier diffusion in the layer and the existence of a region with a short carrier lifetime
near the side boundaries of the layer.
Pis’ma Zh. éksp. Teor. Fiz. 63, No. 7, 523–527 (10 April 1996) 相似文献
8.
V. N. Il'in 《Journal of Applied Spectroscopy》1999,66(6):971-975
An interference method for controlling the refractive index of liquids pumped through a capillary is considered. The liquid
is sounded by two systems of interference bands, the period of which differs by an insignificant value prescribed by the condition
of nonius coincidence. An analytical expression is obtained to calculate the refractive index of the liquid controlled in
automatic reading of the interference patterns.
Institute of Electronics, National Academy of Sciences of Belarus, 22 Logoiskii Trakt, Minsk, 220841, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 6, pp. 832–835, November–December, 1999. 相似文献
9.
Lan Lan Yong Fang Xiaodong Lin Jianguo Chen Dayi Li Guoying Feng 《Optics & Laser Technology》2005,37(3):211-216
First-order approximations have been used to study the recursion expressions of the reflection and transmission coefficients of a weakly absorptive multilayer mirror. It has been proved that in the proximity of the central frequency ω0 of a quarter-wave mirror, contributions of an individual layer to the reflection delay time and absorption-induced reflectivity reduction can be quantitatively specified with a single weighting factor pertinent to that layer. Derivations have indicated that the absorption-induced reductions of mirror reflectivity and reflection delay can be reduced by selecting an odd layer number and a large index ratio between alternating high and low refractive index coating materials. Calculations have also suggested that the absorbed incident light is not distributed, among the reflected and transmitting parts, according to the ratio between the reflectivity and potential transmission. 相似文献
10.
The reflectance of a high-reflectance dielectric multilayer coating mirror tuned to a monochromatic laser wavelength was estimated from its transmittance which was measured with 0.4 ppm accuracy. The transmittance was calculated from its theoretical formula including three parameters (refractive indexes of low and high refractive films (nL, nH) and a number of layer units composed of a pair of one low and one high refractive film (N)) which were estimated from the incident beam angular dependence curve of the transmittance. This calculated transmittance agreed with that measured as a ratio of the laser beam power before and after the mirror with 6 ppm difference. 相似文献
11.
Surface plasmon resonance (SPR) is one of the most sensitive label-free detection methods and has been used in a wide range
of chemical and biochemical sensing. Upon using a 200 nm top layer of dielectric film with a high value of the real part ε′ of the dielectric function, on top of an SPR sensor in the Kretschmann configuration, the sensitivity is improved. The refractive
index effect of dielectric film on sensitivity is usually ignored. Dielectric films with different refractive indices were
prepared by radio frequency magnetron (RF) sputtering and measured with spectroscopic ellipsometry (SE). The imaginary part
ε′′ of the top nanolayer permittivity needs to be small enough in order to reduce the losses and get sharper dips. The stability
of the sensor is also improved because the nanolayer is protecting the Ag film from interacting with the environment. The
response curves of the Ag/ZnO chips were obtained by using SPR sensor. Theoretical analysis of the sensitivity of the SPR
sensors with different ZnO film refractive indices is presented and studied. Both experimental and simulation results show
that the Ag/ZnO films exhibit an enhanced SPR over the pure Ag film with a narrower full width at half maximum (FWHM). It
shows that the top ZnO layer is effective in enhancing the surface plasmon resonance and thus its sensitivity. 相似文献
12.
We have obtained the first experimental evidence for the Pockels effect of water, which is induced by a high electric field in the electric double layer (EDL) on the water-transparent electrode interface. The electric-field induced energy shift of the visible interference fringes of a 300 nm indium-tin-oxide (ITO) electrode layer is observed, indicating a negative refractive index change at the interface. Numerical calculation reproduces well the experimental observation, showing that the signal mainly originates from water in the EDL. The Pockels constants of water are estimated to be r33 = 5.1 × 100 pm/V and r13 = 1.7 × 100 pm/V. The large anisotropy of the Pockels effect of water is deduced from the incidence angle dependence of the p-polarization signal. At the same time, the ITO shows a blue shift of the band gap in the UV due to the band population effect in the space charge layer. The plasma frequency in the near IR is also expected to increase due to the band population effect, since the ITO has a high doped carrier population close to metal. A negative refractive index change in the ITO space charge layer is induced from both effects, but its effect on the signal is estimated to be much smaller than that of the negative refractive index change of water in the EDL. 相似文献
13.
The current — overpotential characteristics of the H2 - Pd - SCY interphase have been studied at atmospheric total pressure and temparatures between 400 – 550 °C in the single
chamber reactor — cell: Pd | SCY | Pd. The results of I−η measurements indicate that the apparent anodic and cathodic charge
tranfer coefficients are equal to: αa=αc=0.5. The present results are compared to those obtained with the single — chamber reactor cell: Ag | SCY | Ag. A solid state
proton (H+) conducting reactor — cell with Pd electrodes was tested for the ammonia synthesis from its elements at atmospheric pressure.
At 570 °C, over 75% of the ectrochemically supplied hydrogen was converted into NH3. The thermodynamic requirement for a high pressure process was eliminated.
Paper presented at the 5th Euroconference on Solid State Ionics, Benalmádena, Spain, Sept. 13–20, 1998. 相似文献
14.
为了探测更高轨道的空间目标,研制了一台通光口径为Ф750 mm的望远镜.该望远镜为主焦点光学系统,由一片二次非球面反射元件和四片透射元件组成,具有大视场(4°),大相对孔径(1∶1.32)和宽光谱(500~800 nm)的特点.本文以该望远镜的研制为基础,介绍了其光学系统各个元件的单独检测和系统装调完成后的整体检测方法和过程.采用样板法对系统中的球面透射元件进行了单独检测,采用透射无像差补偿器法对二次非球面反射镜进行了单独检测,采用反射无像差补偿器法对组合起来的透射校正镜组进行了检测,并且对系统装调对准之后的光学系统进行室内平行光管和室外对星观测两种方法进行检测.测量结果均满足设计要求,其中球面透镜的面形误差小于0.1个光圈,反射元件和透射元件非球面表面的面形误差均优于λ/30(λ=632.8 nm),透射校正镜组的波像差优于λ/30(λ=632.8nm).光学系统整体检测结果表明,室内和室外检测结果一致,其像面的80% 能量集中度直径在4°的全视场范围内均小于2个像元,达到了设计的成像要求. 相似文献
15.
V. N. Il'in 《Journal of Applied Spectroscopy》1997,64(3):403-409
An interference method for measuring the refractive index and surface curvature of cylindrical microlenses is considered.
The method consists in probing microlenses by a dynamic interference pattern with a localization of order of several to tens
micrometers corresponding to the period of the interference fringes. Basic analytical expressions for evaluation of the curvature
radius and refractive index of the probed portion of the microlens are presented.
Institute of Electronics, Academy of Sciences of Belarus, 22, Logoiskii Trakt, Minsk, 220841, Belarus. Translated from Zhurnal
Prikladnoi Spektroskopii, Vol. 64, No. 3, pp. 390–395, May–June, 1997. 相似文献
16.
A method has been proposed for determining the optical properties of a thin film layer on absorbing substrates. The film optical parameters such as thickness, refractive index, absorption coefficient, extinction coefficient and the optical energy gap of an absorbing film are retrieved from the interference fringes of the reflection spectrum at normal incidence. The envelopes of the maxima of the spectrum EM and of the minima Em are introduced in analytical forms to find the reflectance amplitudes at the interfaces and approximate values of the thin film refractive index. Then, the interference orders and film thickness are calculated to get accurate values of the needed optical parameters. There are no complex fitting procedures or assumed theoretical refractive index dispersion relations. The method is applied to calculate the optical properties of an epitaxial gallium nitride thin film on a silicon (1 1 1) substrate. Good agreement between our results and the published data are obtained. 相似文献
17.
18.
I. V. Shirokov 《Russian Physics Journal》1997,40(6):525-530
Formulas for calculating vector fields — generators of groups of transformations to a uniform space — from specified structural
constants are obtained. The problem of vector-field continuation — the construction of Lie algebras of inhomogeneous first-order
differential operators — is considered. It is also shown that the existence of a nontrivial continuation is closely associated
with the structure of the isotopic subalgebra and, in particular, that no nontrivial continuation exists for semisimple algebras.
Omsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 25–32, June, 1997. 相似文献
19.
Wavelength tuning characteristics of a fabry-perot semiconductor laser with an external short cavity
Wavelength tuning characteristics of a Fabry-Perot semiconductor laser with an external short cavity are analyzed, in which
the oscillation wavelength can be changed by slightly altering the external cavity length. Analysis is based on rate equations
for an optical power and carrier density. It is shown that the wavelength tuning range is dominated by a change of carrier
density through the effect of carrier-induced refractive index change in the active layer of a laser diode. This depends on
effective coupling coefficients of the optical field iteratively reflected back to the laser diode by the external mirror,
and on reflection coefficients of an anti-reflection coated laser facet and the external mirror which compose the external
cavity. The effective coupling coefficient is also derived using the waveguide theory and Kirchhoff ’s theory. Finally, an
unstable condition which may limit a stable wavelength tuning range is shown by results of a linear stability analysis of
rate equations. 相似文献