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861.
P. Lougovski H. Walther E. Solano 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,37(3):423-426
We present a method of measuring expectation values of quadrature
moments of a multimode field through two-level probe
“homodyning”. Our approach is based on an integral transform
formalism of measurable probe observables, where analytically
derived kernels unravel efficiently the required field information
at zero interaction time, minimizing decoherence effects. The
proposed scheme is suitable for fields that, while inaccessible to
a direct measurement, enjoy one and two-photon Jaynes-Cummings
interactions with a two-level probe, like spin, phonon, or cavity
fields. Available data from previous experiments are used to
confirm our predictions. 相似文献
862.
O. Sukhoruchko T. Kamyshanova A. Tishchenko 《International Journal of Infrared and Millimeter Waves》2006,27(2):191-198
The paper considers analytical and experimental results on the relative noise temperature and the thermal time constant of
thermoelectric detectors with a point BiSb metal-semimetal contact in the 8-mm wave range. 相似文献
863.
864.
The invariant density of one-dimensional maps in the regime of fully-developed chaos with uncorrelated additive noise is considered.
Boundary conditions are shown to play a significant role in determining the precise form of the invariant density, via the
manner in which they handle the spill-over, caused by the noise, of orbits beyond the interval. The known case of periodic
boundary conditions is briefly recapitulated. Analytic solutions for the invariant density that are possible under certain
conditions are presented with applications to specific well-known maps. The case of ‘sticky’ boundaries is generalized to
‘re-injection at the nearest boundary’, and the exact functional equations determining the invariant density are derived.
Interesting boundary layer effects are shown to occur, that lead to significant modifications of the invariant density corresponding
to the unperturbed (noise-free) case, even when the latter is a constant — as illustrated by an application of the formalism
to the noisy tent map. All our results are non-perturbative, and hold good for any noise amplitude in the interval. 相似文献
865.
866.
867.
868.
利用磁控溅射的方法在氧化后的单晶Si基片上制备了TiNi形状记忆合金薄膜,利用示差扫描量热法和原位X射线衍射研究了薄膜的马氏体相变特征。通过60keV质子注入(辐照)薄膜样品研究了H+离子对合金薄膜马氏体相变特征的影响,结果表明氢离子注入后引起了马氏体相变开始Ms和结束点Mf以及逆马氏体相变开始As和结束温度Af的下降,而对R相变开始Rs和结束温度Rf影响不大。掠入射X射线衍射表明H+离子注入后有氢化物形成。H+离子注入形成的氢化物是引起相变点的变化的主要因素。 相似文献
869.
This paper presents the results of experimental studies of the noise of a residential split-system air-conditioner unit. The compressor and condenser and associated fans were removed from the unit and did not form part of the studies. Care was taken with the unit to separate the inlet and exhaust noise from the noise radiated from the cabinet. The measurements were made with a two-microphone sound intensity probe and these resulted in sound power level data. The sound power levels produced by radiation from the inlet, exhaust and cabinet were obtained for five different volume flow rates. The effect on the sound power generated by removing the coil was investigated. Measurements and subjective studies show that the low frequency sound is predominantly radiated from the exhaust and inlet. At high frequency, the cabinet noise dominates. 相似文献
870.
本文首次尝试利用WKB方法对双噪声原电路的Vander Por方程进行了讨论,并对倍加OU噪声和可加白噪声下的系统进行了数值计算,所得结果对调节含噪声源的电路有一定指导意义。 相似文献