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91.
An automatic aberration correction method has been implemented in scanning electron microscopes (SEM). Necessity of the automatic aberration correction is discussed. The procedure of the automatic aberration correction is explained in detail, where deconvolution techniques are used in order to extract probe information from SEM images. Due to the precise digitization and the usage of proper combinations of correction fields, linearity has been found between the amplitude of each aberration and the corresponding field strength. Experimental results are shown which demonstrate that the aberrations are corrected automatically by a linear feedback control method. After the automatic aberration correction, the image quality has been improved drastically. 相似文献
92.
Kazuya Itsuki Yoshitaka Michihiro Shigeki Endou Koichi Nakamura Takashi Ohno 《Solid State Ionics》2009,180(14-16):917-921
Under the harmonic approximation, the contributions from the indirect ionic interactions to the elastic constants are calculated for the alkali halide and silver halide crystals with the rock-salt structure. The coupling constants of the indirect ionic interactions are calculated by the self-consistent field treatment of the local density approximation and the spherical solid model. The calculated values of the coupling constants are large for the silver ion. The indirect ionic interaction significantly affects the elastic constants. It quantitatively explains the deviation from the Cauchy relation in alkali halide crystals. Moreover, it provides a clear account for the large values of the deviation from the Cauchy relation in AgCl and AgBr. 相似文献
93.
Hiroyuki Kawano Haruhiko Shimoji Shoji Yoshikawa Katsumasa Miyatake Kazumori Hama Shuji Nakamura 《Optical Review》2008,15(2):118-124
Alignment error of an image sensor relative to the optical axis of a star sensor head and alignment errors between four heads
were calculated from pictures taken in an orbital experiment. When comparing the image sensor alignment parameters in the
orbital test and a ground test, both values matched well. By determining the relative relationship of the four heads using
four pictures taken at the same moment in orbit and uploading the parameters to the star sensor system in orbit, the estimated
attitude error was improved from 0.29 to 0.17°, though the accuracy was limited by the ±0.2° determination accuracy of the
satellite itself. We estimated the attitude determination accuracy from separation angles between boresights of the four heads,
calculated from pattern matching between downloaded pictures and a star catalogue. The estimated accuracy, in terms of potential
optical performance, was 0.60 arcmin at 3σ, which is sufficient to satisfy the specification of 1 arcmin. 相似文献
94.
Takayama K Arakida Y Dixit T Iwashita T Kono T Nakamura E Otsuka K Shimosaki Y Torikai K Wake M 《Physical review letters》2007,98(5):054801
We report an experimental demonstration of the induction synchrotron, the concept of which has been proposed as a future accelerator for the second generation of neutrino factory or hadron collider. The induction synchrotron supports a superbunch and a superbunch permits more charge to be accelerated while observing the constraints of the transverse space-charge limit. By using a newly developed induction acceleration system instead of radio-wave acceleration devices, a single proton bunch injected from the 500 MeV booster ring and captured by the barrier bucket created by the induction step voltages was accelerated to 6 GeV in the KEK proton synchrotron. 相似文献
95.
A. Sagisaka A.S. Pirozhkov H. Daido A. Fukumi Z. Li K. Ogura A. Yogo Y. Oishi T. Nayuki T. Fujii K. Nemoto S. Orimo M. Nishiuchi Y. Hayashi M. Mori M. Kado S. Nakamura A. Noda I.W. Choi J.H. Sung D.-K. Ko J. Lee 《Applied physics. B, Lasers and optics》2006,84(3):415-419
A two-color interferometer for preformed plasma characterization is developed. We observe the electron density distribution of preformed plasmas on a 5 μm-thick copper target irradiated with a high-intensity Ti:sapphire laser. The two-color interferometer extended the observable electron density region using a fundamental (800 nm) probe beam to cover the lower density region and a second harmonic (400 nm) probe beam to cover the higher density region, simultaneously. This characterization of the electron density distribution of preformed plasmas with femtosecond time resolution significantly contributes to the understanding of high-intensity laser–thin-foil interactions during high-energy electron, ion, and X-ray generation. PACS 52.38.-r; 52.50.Jm; 52.70.-m 相似文献
96.
97.
Koji Nagata Tadao Nakamura Han Geurdes Josep Batle Soliman Abdalla Ahmed Farouk 《International Journal of Theoretical Physics》2018,57(6):1605-1611
We present a new method of more speedily calculating a multiplication by using the generalized Bernstein-Vazirani algorithm and many parallel quantum systems. Given the set of real values \(\{a_{1},a_{2},a_{3},\ldots ,a_{N}\}\) and a function \(g:\textbf {R}\rightarrow \{0,1\}\), we shall determine the following values \(\{g(a_{1}),g(a_{2}),g(a_{3}),\ldots , g(a_{N})\}\) simultaneously. The speed of determining the values is shown to outperform the classical case by a factor of \(N\). Next, we consider it as a number in binary representation; M1 = (g(a1),g(a2),g(a3),…,g(a N )). By using \(M\) parallel quantum systems, we have \(M\) numbers in binary representation, simultaneously. The speed of obtaining the \(M\) numbers is shown to outperform the classical case by a factor of \(M\). Finally, we calculate the product; \( M_{1}\times M_{2}\times \cdots \times M_{M}. \) The speed of obtaining the product is shown to outperform the classical case by a factor of N × M. 相似文献
98.
Mössbauer spectra of ferrocene derivatives in the solid, adsorption and liquidcrystalline states were measured at temperatures ranging from 78 to 423 K. The peak intensities of the Mössbauer spectra of ferrocene derivatives adsorbed on silica gel decreased markedly with an increase in temperature. The Mössbauer absorption of [4-(4-methoxyphenoxycarbonyl)-phenoxycarbonyl]alkyl 4-ferrocenylbenzoate at 295 K during the cooling process was observed in what was assumed to be the liquid-crystalline state. 相似文献
99.
Yusuke Ishihama Kohji Nakamura Toru Akiyama Tomonori Ito 《Applied Surface Science》2008,254(23):7794-7796
Electronic and magnetic structures of ferromagnetic (FM)/antiferromagnetic (AFM), Ni/FeF2(1 1 0), with a compensated AFM interface are investigated by using the full-potential linearized augmented plane-wave method. We find that magnetic structures at the AFM interface are perturbed by a contact with the FM material, where the superexchange interaction through the interface F excites and induces a small net moment at the AFM interface. These results predicted may play an important role for explaining the exchange bias in this system, and rule out the exchange bias mechanisms with the spin-flop coupling and the magnetic moment reorientation. 相似文献
100.
McKenna J Sayler AM Anis F Gaire B Johnson NG Parke E Hua JJ Mashiko H Nakamura CM Moon E Chang Z Carnes KD Esry BD Ben-Itzhak I 《Physical review letters》2008,100(13):133001
High-order (three-photon or more) above-threshold dissociation (ATD) of H(2)(+) has generally not been observed using 800 nm light. We demonstrate a strong enhancement of its probability using intense 7 fs laser pulses interacting with beams of H(2)(+), HD(+), and D(2)(+) ions. The mechanism invokes a dynamic control of the dissociation pathway. These measurements are supported by theory that additionally reveals, for the first time, an unexpectedly large contribution to ATD from highly excited electronic states. 相似文献