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101.
E. ?ernošková T. Qu Z. ?ernošek P. Boolchand 《Journal of Physics and Chemistry of Solids》2005,66(1):185-189
Thermoanalytical characteristics and Raman scattering of high purity sulfur and ternary bulk glasses GexAsxS(100−2x) for x=4-22 at. % were studied. The intermediate phase characterized by vanishing of non-reversing heat flow ΔHnr, i.e. so-called the thermally reversing window was found between mean coordination number 〈r〉∼2.28-2.47. Separated phase of non-crystalline cycloocta-S, manifesting itself by λ-transition at ∼155 °C, was found for glasses with sulfur content higher than ∼80 at.%. Raman spectra of studied Ge-As-S glasses showed different shapes in three different areas according to three distinct phases of network glasses-floppy, intermediate, rigid. 相似文献
102.
体声波滤波器由于其低插损、小尺寸、高带外抑制等特性,随着第三代移动通信以及蓝牙技术的发展而得到广泛研究,而MEMS技术和压电薄膜制备技术的进一步发展使高性能的体声波滤波器制作成为可能.我们以单晶MgO作为器件衬底,MgO/NbN多层结构作为AIN薄膜体声波器件的反射器,NBN/AIN/NbN三层结构为谐振器.在这样的多层结构的设计中由于各种材料之间的晶格失配小,可以获得从几十纳米到几百纳米厚度不等的单晶AIN薄膜.通过控制AIN薄膜和NbN薄膜的不同厚度,可以获得不同频段范围的谐振器.压电薄膜的质量,以及体声波在多层结构界面上的能量损耗,直接影响到谐振器电学性能.基于AIN材料的压电性能,设计了NBN/AIN/NBN三层结构的谐振器,并进行了数值模拟. 相似文献
103.
Ban G Bodek K Daum M Henneck R Heule S Kasprzak M Khomutov N Kirch K Kistryn S Knecht A Knowles P Kuźniak M Lefort T Mtchedlishvili A Naviliat-Cuncic O Plonka C Quéméner G Rebetez M Rebreyend D Roccia S Rogel G Tur M Weis A Zejma J Zsigmond G 《Physical review letters》2007,99(16):161603
In case a mirror world with a copy of our ordinary particle spectrum would exist, the neutron n and its degenerate partner, the mirror neutron n', could potentially mix and undergo nn' oscillations. The interaction of an ordinary magnetic field with the ordinary neutron would lift the degeneracy between the mirror partners, diminish the n' amplitude in the n wave function and, thus, suppress its observability. We report an experimental comparison of ultracold neutron storage in a trap with and without superimposed magnetic field. No influence of the magnetic field is found and, assuming negligible mirror magnetic fields, a limit on the oscillation time taunn' > 103 s (95% C.L.) is derived. 相似文献
104.
This paper describes a novel fiber-coupled heterodyne interferometer using a micro-electro-mechanical system (MEMS) mirror
and an f-theta lens. In this interferometer system, the cross-polarized laser beams operating at 2 μm with the frequency difference
of 100 kHz are introduced by means of the two acousto-optic modulators (AOM). The sample with diameter of 300 mm is uniformly
scanned by the 1 mm laser beam with the help of the combined optical scanning configuration, a MEMS mirror and an f-theta
lens. The output intermediate signal from the two channels, reference channel and the measurement channel, are processed in
the 12 bit analog-to-digital (A/D) process system. Details of our interferometer scheme are discussed. 相似文献
105.
Using the vertical evaporation technique we fabricated saturable absorbers by transferring the double-wall carbon nanotubes
(DWCNT) onto a hydrophilic quartz substrate. The fast recovery time and the saturation intensity of the absorber were measured
to be 228 fs and 130 μJ/cm2, respectively, at 1060 nm. The modulation depth of the absorber was about 3.7%. Passive mode-locked Nd:GdVO4 laser was demonstrated. The continuous wave mode-locked pulses pulse duration is 5.6 ps and the largest average output power
is 1.2 W at the pump power of 9.5 W. To the best of our knowledge, this is the first demonstration of high power continuous
wave mode locking laser with DWCNT absorber. 相似文献
106.
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109.
We study spiral wave breakup using a Fitzhugh-Nagumo-type system. We find that spiral wave breakup can occur near the core or far from it in both excitable and oscillatory regimes. There is a faraway breakup scenario in both excitable and oscillatory media that depends on long wavelength modulation modes. We observed three distinct scenarios, including one that involves breakup that does not develop into turbulence. However, we find that the mechanisms behind these three scenarios are the same: they are caused by the interaction between the dispersion relation and the asymptotic behavior of the modulation mode. The difference in phenomenology is due to the asymptotic behavior of the modulation mode. 相似文献
110.