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91.
92.
Takaaki Kakitsuka Shinji Matsuo Seok–Hwan Jeong Toru Segawa Hiroshi Okamoto Yoshihiro Kawaguchi Yasuhiro Kondo Yuzo Yoshikuni Hiroyuki Suzuki 《Optical and Quantum Electronics》2006,38(12-14):1053-1060
We theoretically investigated a digitally tunable laser with a chirped ladder filter and a ring resonator to obtain a wide wavelength tuning range covering the whole C- or L- band. The clear relation between the tuning range and laser structure, especially the ladder filter, is described analytically. The introduction of a chirped structure into a ladder filter is effective in achieving both wide tunability and a stable lasing mode. A numerical simulation based on multimode rate equations shows that a tuning range of over 40 nm and a mode suppression ratio over 40 dB can be achieved by introducing a chirped ladder filter. 相似文献
93.
Keisuke Fujikawa Shushi Suzuki Yuichiro Koike Wang-Jae Chun Kiyotaka Asakura 《Surface science》2006,600(10):117-121
We have studied the growth mode and morphology of Ni clusters on a TiO2(1 1 0) surface with a wide terrace using scanning tunneling microscopy (STM) at a low coverage (less than 3 atoms nm−2). The Ni clusters are formed on the terrace at the low coverage of 0.2 atoms nm−2. Their average dimensions are constant in three directions up to 1 atoms nm−2. The Ni clusters have an oval shape with average sizes of 1.8 nm (along [0 0 1]) × 1.4 nm (along (in the [1 1 0] directions). Above the coverage of 1.0 atoms nm−2, an increase in the cluster height occurs, retaining an almost constant lateral size. It is proposed that the interaction of the Ni cluster and the support surface regulates the Ni cluster size. 相似文献
94.
Adsorption structures of the pentacene (C22H14) molecule on the clean Si(0 0 1)-2 × 1 surface were investigated by scanning tunneling microscopy (STM) in conjunction with density functional theory calculations and STM image simulations. The pentacene molecules were found to adsorb on four major sites and four minor sites. The adsorption structures of the pentacene molecules at the four major sites were determined by comparison between the experimental and the simulated STM images. Three out of the four theoretically identified adsorption structures are different from the previously proposed adsorption structures. They involve six to eight Si-C covalent chemical bonds. The adsorption energies of the major four structures are calculated to be in the range 67-128 kcal/mol. It was also found that the pentacene molecule hardly hopped on the surface when applying pulse bias voltages on the molecule, but was mostly decomposed. 相似文献
95.
Wavelet processing and digital interferometric contrast to improve reconstructions from X‐ray Gabor holograms 下载免费PDF全文
Juan C. Aguilar Masaki Misawa Kiyofumi Matsuda Yoshio Suzuki Akihisa Takeuchi Masato Yasumoto 《Journal of synchrotron radiation》2018,25(3):808-817
In this work, the application of an undecimated wavelet transformation together with digital interferometric contrast to improve the resulting reconstructions in a digital hard X‐ray Gabor holographic microscope is shown. Specifically, the starlet transform is used together with digital Zernike contrast. With this contrast, the results show that only a small set of scales from the hologram are, in effect, useful, and it is possible to enhance the details of the reconstruction. 相似文献
96.
Sho Hayakawa Taira Okita Mitsuhiro Itakura Masaatsu Aichi Katsuyuki Suzuki 《哲学杂志》2018,98(25):2311-2325
We conduct kinetic Monte Carlo simulations for the conservative climb motion of a cluster of self-interstitial atoms (SIAs) towards another SIA cluster in BCC–Fe; the conservative climb velocity is inversely proportional to the fourth power of the distance between them, as per the prediction based on Einstein’s equation. The size of the climbing cluster significantly affects its conservative climb velocity, while the size of the cluster that originates the stress field does not. The activation energy for the conservative climb is considerably greater than that derived in previous studies and strongly dependent on the climbing cluster size. The results presented in this study are the atomistic evaluation of the behaviour of SIA clusters through three-dimensional motion, which cannot be achieved using molecular dynamics techniques alone. 相似文献
97.
Asobe M Tadanaga O Umeki T Yanagawa T Nishida Y Magari K Suzuki H 《Optics letters》2007,32(23):3388-3390
We propose a novel quasi-phase-matched (QPM) device that can generate unequally spaced multiple wavelengths. Unequally spaced multiple QPM peaks can be obtained by employing the optimized phase modulation of a periodic domain structure. We fabricated a LiNbO3 waveguide device for 3.2-3.4 microm band difference frequency generation based on the design. Using the multiple mid-infrared outputs, we demonstrate the detection of multiple hydrocarbon gases, namely, methane, ethylene, and ethane. 相似文献
98.
We grew SrTiO(3) on SrTiO(3)(001) by pulsed laser deposition, while observing x-ray diffraction at the (00(1/2)) position. The drop DeltaI in the x-ray intensity following a laser pulse contains information about plume-surface interactions. Kinematic theory predicts DeltaI/I = -4sigma(1 - sigma), so that DeltaI /I depends only on the amount of deposited material sigma. In contrast, we observed experimentally that |DeltaI /I| < 4sigma(1 - sigma) and that DeltaI /I depends on the phase of x-ray growth oscillations. The combined results suggest a fast smoothing mechanism that depends on surface step-edge density. 相似文献
99.
H. Kira Y. Sakaguchi T. Oku J. Suzuki M. Nakamura M. Arai K. Kakurai Y. Endo Y. Arimoto T. Ino H.M. Shimizu T. Kamiyama K. Tsutsumi K. Ohoyama H. Hiraka K. Yamada L.-J. Chang 《Physica B: Condensed Matter》2011,406(12):2433-2435
We have begun the development of an in-situ spin-exchange optical pumping (SEOP) system aiming to use it as a neutron spin filter for incident beam polarization at the Japan Proton Accelerator Research Complex (J-PARC). To use it, it is recommended that the optics be adjusted easily, have high stability, and have a small size. In this paper we improved our previous SEOP system aiming to use it in J-PARC and performed a neutron beam test at the JRR-3 NOP beamline to see the performance of the neutron spin filter (NSF). The polarization of the 3He gas reached 73%. This paper gives the present status of the development of in-situ SEOP system in J-PARC. 相似文献
100.
T. Ino Y. ArimotoT. Yoshioka K. MishimaK. Taketani S. MutoH.M. Shimizu H. KiraY. Sakaguchi T. OkuK. Sakai T. ShinoharaJ. Suzuki H. OtonoH. Oide S. YamashitaS. Imajo H. FunahashiM. Yamada Y. IwashitaM. Kitaguchi M. HinoZ. Suzuki T. SanukiT. Seki K. HirotaK. Ikeda H. SatoY. Otake H. OhmoriT. Morishima T. Shima 《Physica B: Condensed Matter》2011,406(12):2424-2428
We measured the neutron beam polarization of the BL05/NOP (Neutron Optics and Physics) beamline at J-PARC with an accuracy of less than 10−3 using polarized 3He gas as a neutron spin analyzer. Precise polarimetry of the neutron beam is necessary to understand the beamline optics as well as for the asymmetry measurements of the neutron beta decay, which are planned in this beamline. 相似文献