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71.
Microresonator filters, which are realized by evanescent coupling of circular cavities with two parallel bus waveguides, are promising candidates for applications in dense wavelength-division multiplexing. Tunability of these filters is an essential feature for their successful deployment. In this paper, we present a framework for modeling of tuning of the microresonators by changes in their cavity core refractive index. Using a reciprocity theorem, a perturbational expression for changes in the cavity propagation constants due to slight modifications of the cavity core refractive index is derived. This expression permits us to analytically calculate shifts in the spectral response of the 2-D resonators. Comparisons of the resultant shifts and spectra with direct simulations based on a coupled mode theory show satisfactory agreement. 相似文献
72.
G. V. Ivanenkov S. A. Pikuz T. A. Shelkovenko J. Greenly D. B. Sinars D. A. Hammer 《Journal of Experimental and Theoretical Physics》2000,91(3):469-478
Data from high-resolution x-ray shadow photography of an X-pinch in the diode of a high-power dense-plasma generator are presented. The processes leading to the formation of a minidiode, the compression of the neck arising in it, and the cutoff and subsequent emptying of the neck are studied. Cascade formation of short-lived structures, which consistently reproduce the form of the minidiode on small scales before the x-ray burst, is observed in the course of the implosion. The position of the x-ray emission points is determined. 相似文献
73.
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76.
Wen C. Hammer J. Gorog I. Spong F. van Raalte J. 《Quantum Electronics, IEEE Journal of》1966,2(11):711-713
The electrooptic effect is utilized to produce a number of types of internal laser color switches. Initial experiments have shown that the primary colored (red, green, blue) lasing lines of the Kr+laser can be switched. 相似文献
77.
Delanson R. Crist Chung-Hua Li Charles F. Hammer Keith A. Nelson Horst G. Adolph 《Journal of heterocyclic chemistry》1994,31(6):1525-1528
The base-promoted addition of glyoxal to 1,1,2,2-tetrakis(ethoxycarbonylamino)ethane in DMF gives a product mixture containing mostly 1,1′,3,3′-tetrakis(ethoxycarbonyl)-4,4′,5,5,'-tetrahydroxy-2,2′-biimidazolidyl. An alternate structure containing a tetraazadecalin system was considered less likely, since the most significant peak in the mass spectrum of this product and a tetraacetate derivative corresponded to half the mass of the parent ion. Two-dimensional nmr spectra on the major hplc fraction are more consistent with the biimidazolidinyl structure (very low Jvic and lack of NOE enhancement). A HETCOSY spectrum on the mixture allowed assignment of 1H nmr shifts. 相似文献
78.
In the paper the mathematical methods for dead-time and pile-up corrections are discussed. The dead-time correction formulae
for a system of two short-lived isotopes and constant component (background) are reported which mathematical problem has not
been solved so far. The new electronic circuit for simultaneous measurements of clock- and live- (or dead-) times is described.
It is shown that using this circuit one can correct the counting loss for both effects simultaneously. Finally, the advantages
and disadvantages of mathematical methods for dead-time and pile-up corrections are discussed based on the authors' several-year
laboratory practice. 相似文献
79.
Volker Gehrling J. Wolfgang Hammer Klaus -Werner Hoffmann 《Zeitschrift für Physik A Hadrons and Nuclei》1971,246(5):376-382
The electron capture decay and the positron decay of84Rb were investigated using NaJ (Tl)-detectors and a Ge (Li)-detector. Measurements of all intensities and of some informative double and triple coincidences were performed. From coincidence measurements betweenK-X-radiation and the following γ-radiation we got theK-fluorescence yield of Krypton ΩitK=0.653 ± 0.004. Taking in consideration former measurements1 one concludes a continuous behaviour of ΩitK(Z) forZ=36, 37 and 38 within an uncertainty of 1%. For the branching ratios of the decay of84Rb we obtained The half-life of84Rb was determined to beT 1/2=(34.5 ± 0.2) d. 相似文献
80.