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941.
A design method along with its results, for a space optical system with high resolution and wide field of view, is described. Such optical systems can be used in the infrared as well as visible configurations. The proposed design is based on an on-axis Ritchey-Chrétien system with corrected lens element while the primary mirror is a segmented aperture. Here the on-axis concept allows wide-field enabling a variety of observations designed for the multi-object spectrometer instruments, optimized for low scattering and low emission of light. The use of segmented mirrors in the optical system allows adopting any method for its fabrication purposes. Segment results are discussed and the image quality of the design based on these results is evaluated in this paper. 相似文献
942.
943.
944.
The influence of the width of a lattice-matched Al0.82In0.18N/GaN single quantum well (SQW) on the absorption coefficients and wavelength of the intersubband transition (ISBT) has been investigated by solving the Schrödinger and Poisson equations self-consistently. The wavelength of 1—2 ISBT increases with L, the thickness of the single quantum well, ranging from 2.88 μm to 3.59 μm. The absorption coefficients of 1—2 ISBT increase with L at first and then decrease with L, with a maximum when L is equal to 2.6 nm. The wavelength of 1—3 ISBT decreases with L at first and then increases with L, with a minimum when L is equal to 4 nm, ranging from approximately 2.03 μm to near 2.11 μm. The absorption coefficients of 1—3 ISBT decrease with L. The results indicate that mid-infrared can be realized by the Al0.82In0.18N/GaN SQW. In addition, the wavelength and absorption coefficients of ISBT can be adjusted by changing the width of the SQW. 相似文献
945.
C. B. Li Y. Zheng X. G. Wu X. F. Li C. Y. He G. S. Li S. H. Yao B. B. Yu X. P. Cao S. P. Hu J. L. Wang J. B. Lu Y. J. Ma D. Yang H. D. Wang K. Y. Ma G. Y. Liu L. Li C. Xu Y. Y. Cheng 《The European Physical Journal A - Hadrons and Nuclei》2011,47(11):1-7
High-spin states in 114In were populated using the reaction 110Pd(7Li, 3n)114In at a beam energy of 26MeV. The level scheme of 114In consisting of six bands is established up to excitation energy ~ 5MeV and spin ~ 17 ? with the addition of 58 new transitions and their configurations are discussed. The intense positive-parity dipole cascade may be interpreted as shears band based on $ \pi$ [(g 9/2)-1] ? $ \nu$ [(g 7/2/d 5/2)(h 11/2)2] configuration. The $ \Delta$ I = 2 bands based on proton excitation have been observed in 114In for the first time. 相似文献
946.
X. Li X. Cao 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,64(2-3):221-225
Quantum chemical calculations of the structure and stability of MNg 4 2+ (M = Cu, Ag and Au; Ng = He and Ne) series at the CCSD(T) theoretical level are performed. The interaction mechanism is investigated using the natural bond orbital (NBO) and electron density analyses. The analyses of the electron density show the weak electrostatic interaction in the system. 相似文献
947.
The third-order ghost imaging with the second-order intensity correlation is theoretically and experimentally demonstrated.The resolution and visibility of the reconstructed image are discussed,and the relationship between resolution and visibility is analyzed.The theoretical results show that a tradeoff exists between the visibility and resolution of the reconstructed image;the better the image resolution,the worse the image visibility.Numerical simulations are carried out to verify this theory,and a ghost... 相似文献
948.
We experimentally investigate the transmission performance of 60-GHz signals over standard single-mode fiber (SSMF) and wireless links at different bit rates. Experimental results show that in a transmission of over 10-km SSMF and 1.3-m wireless link, bit rate reaches up to 5 Gb/s and bit error rate (BER) is less than 10 4 . The main limiting factor in such radio-over-fiber (ROF) systems is intersymbol interferences caused by the so-called walk-off effect when BER is below 10 8 . In addition, a transmission of over 20-km SSMF without chromatic dispersion compensation is briefly investigated. For a BER of 10 8 , the optical penalty is 2 dB. 相似文献
949.
Open-circuit voltage analysis of p-i-n type amorphous silicon solar cells deposited at low temperature 下载免费PDF全文
This paper identifies the contributions of p-a-SiC:H layers and i-a-Si:H layers to the open circuit voltage of p-i-n type a-Si:H solar cells deposited at a low temperature of 125 C.We find that poor quality p-a-SiC:H films under regular conditions lead to a restriction of open circuit voltage although the band gap of the i-layer varies widely.A significant improvement in open circuit voltage has been obtained by using high quality p-a-SiC:H films optimized at the "low-power regime" under low silane flow rates and high hydrogen dilution conditions. 相似文献
950.
D. Cao Q. Peng S. Du J. Xu Y. Guo J. Yang Y. Bo J. Zhang D. Cui Z. Xu 《Applied physics. B, Lasers and optics》2011,103(1):83-88
A water-cooled 785 nm diode-side-pumped high-power CW Tm:YAG laser system at 2 μm is reported. 200 W output power is achieved
with cooling water running at 8°C. As far as we know, this is the highest output power for a diode-pumped all solid-state
2 μm Tm:YAG laser. The output corresponds to optical-to-optical conversion efficiency of 11.2%, with a slope efficiency of
about 22.8%. To make the system structure simple, only deionized water is used as the coolant instead of alcohol- or glycol-water
mixture or the liquid nitrogen in the reported high-power Tm rod laser experiments, which were performed at low temperature
near the freezing point of water, or even below. 相似文献