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51.
Jen-Hwan Tsai 《Journal of luminescence》2010,130(10):1680-1686
In this paper, a shift in the photoluminescence (PL) peak from blue to near-infrared region was observed in the Si+-implanted 400-nm-thick SiO2 films with the rapid thermal annealing (RTA) method only. As the Si+-fluence was 1×1016 ions/cm2, a blue band was observed in the films after RTA at 1050 °C for 5 s in dry-N2 atmosphere; then, the band shifted from blue to orange upon increasing the holding temperature of RTA to 1250 °C in the films after the isochronal RTA in dry N2. Furthermore, while the fluence was increased to 3×11016 ions/cm2 and the holding temperature was at the same range between 1050 and 1250 °C, the PL peak occurred between red and near-infrared regions. Although the RTA and conventional thermal annealing (CTA) methods produce a similar mechanism, the CTA method needs a much longer annealing-time and a higher Si+-implanted dose than the RTA method for producing the same shift and intensity of PL peak from the as-implanted sample. Therefore, the RTA method can produce the mechanism in the Si+-implanted sample with the PL energy between blue and near-infrared band in place of the CTA method. 相似文献
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The transition from disorder to order in Ag film grown on Au(111) was investigated by monitoring the quantum well states using angle-resolved photoelectron spectroscopy. Our results show that the binding energies do not alter, but the in-plane dispersion alters from flat to parabolic when the film is annealed. We suggest that there are isolated and ordered patches scattered across the film at an early stage of the transition and that atoms inside the patches are fully ordered along the surface normal. These ordered patches grow and merge together as the annealing temperature increases. 相似文献
54.
Y. Hwu W. L. Tsai B. Lai J. H. Je G. H. Fecher M. Bertolo G. Margaritondo 《Surface science》2001,480(3):188-195
We present several successful test cases of using photoelectron emission microscopy (PEEM) for photon energy up to 25 keV. First, the full extended X-ray absorption fine structure analysis was implemented in areas as small as 100 μm2 for transition-metal K edge absorption spectra and, therefore, demonstrated the feasibility of combining structural and chemical analysis with hard-X-ray absorption spectroscopy with high lateral resolution. We also show that PEEM can be used in a transmission (radiography) mode as an imaging detector for hard-X-ray. This approach again leads to the unprecedented 0.3 μm lateral resolution, particularly critical for the use of coherence-based phase contrast techniques in real time X-ray radiology. 相似文献
55.
Tsai Chia-Wei Lin Jason Chiu Lung Yang Chun-Wei 《International Journal of Theoretical Physics》2021,60(9):3599-3608
International Journal of Theoretical Physics - Ma et al. [Int. J. Theor. Phys. (2021): 1328–1338] proposed a multi-party quantum key distribution (MQKD) protocol using Bell states, in which... 相似文献
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Discrimination of basal cell carcinoma from normal dermal stroma by quantitative multiphoton imaging
Lin SJ Jee SH Kuo CJ Wu RJ Lin WC Chen JS Liao YH Hsu CJ Tsai TF Chen YF Dong CY 《Optics letters》2006,31(18):2756-2758
We performed multiphoton fluorescence (MF) and second-harmonic generation (SHG) imaging on human basal cell carcinoma samples. In the dermis, basal cell carcinomas can be identified by masses of autofluorescent cells with relatively large nuclei and marked peripheral palisading. In the normal dermis, SHG from dermal collagen contributes largely to the multiphoton signal. However, within the cancer stroma, SHG signals diminish and are replaced by autofluorescent signals, indicating that normal collagen structures responsible for SHG have been altered. To better delineate the cancer cells and cancer stroma from the normal dermis, a quantitative MF to SHG index is developed. We demonstrate that this index can be used to differentiate cancer cells and adjacent cancer stroma from the normal dermis. Our work shows that MF and SHG imaging can be an alternative for Mohs' surgery in the real-time guidance of the secure removal of basal cell carcinoma. 相似文献
60.
Chia‐Wei Chu Xiaomin Zhai Chih Jie Lee Po‐Hao Wang Yubo Duan Din Ping Tsai Baile Zhang Yuan Luo 《Laser \u0026amp; Photonics Reviews》2015,9(4):399-404
Transformation optics, a recent geometrical design strategy of light manipulation with both ray trajectories and optical phase controlled simultaneously, promises an invisibility cloaking device that can render a macroscopic object invisible even to a scientific instrument measuring optical phase. Recent “carpet” cloaks have extended their cloaking capability to broadband frequency ranges and macroscopic scales, but they only demonstrated the recovery of ray trajectories after passing through the cloaks, while whether the optical phase would reveal their existence still remains unverified. In this paper, a phase‐preserved macroscopic visible‐light carpet cloak is demonstrated in a geometrical construction beyond two dimensions. As an extension of previous two‐dimensional (2D) macroscopic carpet cloaks, this almost‐three‐dimensional carpet cloak exhibits three‐dimensional (3D) invisibility for illumination near its center (i.e. with a limited field of view), and its ideal wide‐angle invisibility performance is preserved in multiple 2D planes intersecting in the 3D space. Optical path length is measured with a broadband pulsed‐laser interferometer, which provides unique experimental evidence on the geometrical nature of transformation optics.