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71.
Novel electron-optical components and concepts aiming at improving the throughput and extending the applications of a low energy electron microscope (LEEM) have been developed. An immersion magnetic objective lens can substantially reduce e-e interactions and the associated blur, as electrons do not form a sharp crossover in the back-focal plane. The resulting limited field of view of the immersion objective lens in mirror mode can be eliminated by immersing the cathode of the electron gun in a magnetic field. A dual illumination beam approach is used to mitigate the charging effects when the LEEM is used to image insulating surfaces. The negative charging effect, created by a partially absorbed mirror beam, is compensated by the positive charging effect of the secondary beam with an electron yield exceeding 1. On substrates illuminated with a tilted beam near glancing incidence, large shadows are formed on even the smallest topographic features, easing their detection. On magnetic substrates, the magnetic flux leaking above the surface can be detected with tilted illumination and used to image domain walls with high contrast. 相似文献
72.
Abbasi RU Abu-Zayyad T Amann JF Archbold G Bellido JA Belov K Belz JW Bergman DR Cao Z Clay RW Cooper MD Dai H Dawson BR Everett AA Fedorova YA Girard JH Gray RC Hanlon WF Hoffman CM Holzscheiter MH Hüntemeyer P Jones BF Jui CC Kieda DB Kim K Kirn MA Loh EC Manago N Marek LJ Martens K Martin G Matthews JA Matthews JN Meyer JR Moore SA Morrison P Moosman AN Mumford JR Munro MW Painter CA Perera L Reil K Riehle R Roberts M Sarracino JS Sasaki M Schnetzer SR Shen P Simpson KM Sinnis G Smith JD 《Physical review letters》2004,92(15):151101
We have measured the cosmic ray spectrum above 10(17.2) eV using the two air-fluorescence detectors of the High Resolution Fly's Eye observatory operating in monocular mode. We describe the detector, phototube, and atmospheric calibrations, as well as the analysis techniques for the two detectors. We fit the spectrum to a model consisting of galactic and extragalactic sources. 相似文献
73.
74.
Trond Bjørndal Veijo Kaitala Marko Lindroos Gordon R. Munro 《Annals of Operations Research》2000,94(1-4):183-196
The intergovernmental United Nations Conference on Highly Migratory and Straddling Stocks, initiated in 1993 and finished in 1995, addressed the conservation and management of fishery resources located both within the coastal state 200 mile Exclusive Economic Zone (EEZ) and the adjacent high seas. These types of marine resources continue to be a source for international conflicts and debates. The original United Nations Law of the Sea of 1982 failed to address transboundary fisheries in a proper way. In particular, the agreement did not recognize the emergence of the complicated straddling stock issue. In the new United Nations Law of the Sea agreement of 1995, a consensus was reached that the management of the straddling and highly migratory fish stocks should be carried out through regional fisheries management organizations. We present a review of the straddling stock issues in the international agreement emerging from the negotiations within the United Nations. The review is contrasted with and clarified by game theoretic analyses. We also discuss one international fishery exemplifying the case, the Norwegian springspawning herring. The main conclusion is that the local problems, faced during the stage of setting up regional fisheries organizations for the management of straddling and highly migratory fish stocks, are expected to be much more complicated and difficult to solve as compared to the cases of shared fish stocks. In the current paper, we present two reasons for this increased complexity. The first is the larger number of players as compared to the case of shared fish stocks and the second is the possibility of new members entering the regional fisheries organizations. 相似文献
75.
S.S. Hasnain T.D.S. Hamilton I.H. Munro E. Pantos 《Journal of Molecular Spectroscopy》1978,72(3):406-422
Absorption and luminescence excitation spectra of solid benzene and benzene isolated in rare-gas matrices have been studied. The absolute absorption cross sections of various electronic band systems including the Rydberg region of C6H6 are obtained using transmission spectra of C6H6-doped rare-gas films of different thickness. An interpretation of the structure in the Rydberg region is given in terms of two Rydberg series using the quantum defect method. A comparative study has been made of luminescence excitation spectra of matrix-isolated and of pure C6H6. The luminescence excitation spectra of matrix-isolated benzene gives information on the internal conversion and medium-induced vibrational relaxation. 相似文献
76.
77.
We propose a method for quantum information processing using molecules coupled to an external laser field. This utilizes molecular interactions, control of the external field, and an effective energy shift of the doubly excited state of two coupled molecules. Such a level shift has been seen in the two-photon resonance experiments recently reported by Hettich et al. Here we show that this can be explained in terms of the QED Lamb shift. We quantify the performance of the proposed quantum logic gates in the presence of dissipative mechanisms. The unitary transformations required for performing one- and two-qubit operations can be implemented with present day molecular technology. The proposed techniques can also be applied to coupled quantum dot and biomolecular systems. 相似文献
78.
A. I. Lebedev A. V. Michurin I. A. Sluchinskaya V. N. Demin I. Munro 《Crystallography Reports》2000,45(4):555-559
The local environment of Ga, Tl, and Se atoms in InTe-based solid solutions have been studied by the method of EXAFS spectroscopy. It is shown that these atoms can be regarded as substitutional impurities occupying the In(1), In (2), and Te positions in the InTe structure. Electric measurements showed that the In1-x GaxTe and InTe1-x Sex solid solutions are semiconductors at x > 0.24 and x > 0.15, respectively. 相似文献
79.
Sadia Sultan Lin Sun John W. Blunt Anthony L.J. Cole Murray H.G. Munro Kalavathy Ramasamy Jean-Frédéric F. Weber 《Tetrahedron letters》2014
Two further lasiodiplodins, (3R,4R)-4-hydroxy-de-O-methyl-lasiodiplodin and (E)-9-etheno-de-O-methyl-lasiodiplodin, together with three known lasiodiplodins from a cytotoxic extract obtained from a culture of Lasiodiplodia theobromae, an endophyte from the root tissues of Mapania kurzii (Cyperaceae) from the Malaysian rain forest, were characterized on microgram scale. 相似文献
80.
We present an improved phase estimation scheme employing entangled coherent states and demonstrate that these states give the smallest variance in the phase parameter in comparison to NOON, "bat," and "optimal" states under perfect and lossy conditions. As these advantages emerge for very modest particle numbers, the optical version of entangled coherent state metrology is achievable with current technology. 相似文献