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61.
Frequency differences of up to 170 GHz between a cw dye laser and a krypton laser at 568 nm were measured by mixing laser and microware radiation with a metalinsulator-metal point contact diode. Beat signals are well above noise and there is still great potential for improvement when better microwave oscillators are used. From the measurements reported it follows that the diode can be used for determining still higher frequency differences of visible laser radiation. 相似文献
62.
zur Capellen Walther Meyer 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1960,11(3):207-218
Summary The rotational energy of a link in a mechanism is proportional to the square of its angular velocity. This square, in contrast to the angular velocity itself, can be expanded into a Fourier series, having finite values for its coefficients. The problem is solved by splitting it into partial fractions, leading to the harmonic analysis of the slotted lever mechanism. Further related series are given at the end. 相似文献
63.
We have performed the first experimental tomographic reconstruction of a three-photon polarization state. Quantum state tomography is a powerful tool for fully describing the density matrix of a quantum system. We measured 64 three-photon polarization correlations and used a "maximum-likelihood" reconstruction method to reconstruct the Greenberger-Horne-Zeilinger state. The entanglement class has been characterized using an entanglement witness operator and the maximum predicted values for the Mermin inequality were extracted. 相似文献
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Bartholomy O Credé V van Pee H Anisovich AV Anton G Bantes R Beloglazov Y Bogendörfer R Castelijns R Ehmanns A Ernst J Fabry I Flemming H Fösel A Freiesleben H Fuchs M Funke Ch Gothe R Gridnev A Gutz E Höffgen SK Horn I Hössl J Joosten R Junkersfeld J Kalinowsky H Klein F Klempt E Koch H Konrad M Kopf B Krusche B Langheinrich J Löhner H Lopatin I Lotz J Matthäy H Menze D Messchendorp J Morales C Novinski D Ostrick M Radkov A Reinnarth J Sarantsev AV Schadmand S Schmidt Ch Schmieden H Schoch B 《Physical review letters》2005,94(1):012003
Single pi(0) photoproduction has been studied with the CB-ELSA experiment at Bonn using tagged photon energies between 0.3 and 3.0 GeV. The experimental setup covers a very large solid angle of approximately 98% of 4pi. Differential cross sections dsigma/dOmega have been measured. Complicated structures in the angular distributions indicate a variety of different resonances being produced in the s channel intermediate state gammap-->N(*)(Delta(*))-->ppi(0). A combined analysis including the data presented in this letter along with other data sets reveals contributions from known resonances and evidence for a new resonance N(2070)D15. 相似文献
65.
We propose a scheme for slowing down decay into a continuum. We make use of a sequence of ultrashort 2pi pulses applied on an auxiliary transition of the system so that there is a destructive interference between the two transition amplitudes--one before the application of the pulse and the other after the application of the pulse. We give explicit results for a structured continuum. Our scheme can also inhibit unwanted transitions. 相似文献
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Dirk Walther 《Journal of organometallic chemistry》1980,190(4):393-401
Nickel(O) complex moieties with a high electron density at the central atom are able to yield stable complexes with many aromatic aldehydes. 1H NMR spectroscopic data give evidence about olefin-like bonding of the aldehyde group and indicate a high charge transfer. Chelate ligands like tetramethylethylenediamine yield stable complexes of the composition (TME)NiL (L = aldehyde, benzil, ,β-unsaturated carbonyl compounds). Some reactions and properties of typical mixed ligand complexes are described. 相似文献