An ultrathin micro-split Jerusalem-cross metasurface is proposed in this paper, which can efficiently convert the linear polarization of electromagnetic （EM） wave into the circular polarization in ultra-wideband. By...An ultrathin micro-split Jerusalem-cross metasurface is proposed in this paper, which can efficiently convert the linear polarization of electromagnetic （EM） wave into the circular polarization in ultra-wideband. By symmetrically employing two micro-splits on the horizontal arm （in the x direction） of the Jerusalem-cross structure, the bandwidth of the proposed device is significantly extended. Both simulated and experimental results show that the proposed metasurface is able to convert linearly polarized waves into circularly polarized waves in a frequency range from 12.4 GHz to 21 GHz, with an axis ratio better than 1 dB. The simulated results also show that such a broadband and high-performance are maintained over a wide range of incident angle. The presented polarization converter can be used in a number of areas, such as spectroscopy and wireless communications.展开更多
The influence of the gap on the absorption performance of the conventional split ring resonator(SRR) absorber is investigated at microwave frequencies. Our simulated results reveal that the geometry of the square SRR ...The influence of the gap on the absorption performance of the conventional split ring resonator(SRR) absorber is investigated at microwave frequencies. Our simulated results reveal that the geometry of the square SRR can be equivalent to a Jerusalem cross(JC) resonator and its corresponding metamaterial absorber(MA) is changed to a JC absorber. The JC MA exhibits an experimental absorption peak of 99.1% at 8.72 GHz, which shows an excellent agreement with our simulated results. By simply assembling several JCs with slightly different geometric parameters next to each other into a unit cell, a perfect multi-band absorption can be effectively obtained. The experimental results show that the MA has four distinct and strong absorption peaks at 8.32 GHz, 9.8 GHz, 11.52 GHz and 13.24 GHz. Finally, the multi-reflection interference theory is introduced to interpret the absorption mechanism.展开更多
This essay employs the approach of New Criticism close reading to interpret My Jerusalem by a contemporary Chinese poet, Wang Guilin, from the dialogic perspective of＂I and Thou.＂ From a dimension of faith beyond da...This essay employs the approach of New Criticism close reading to interpret My Jerusalem by a contemporary Chinese poet, Wang Guilin, from the dialogic perspective of＂I and Thou.＂ From a dimension of faith beyond daily life, the poet narrates his astonishment, historical reflection and spiritual transformation during a visit to Jerusalem. For him, the journey to Jerusalem was also a pilgrimage to a spiritual homeland, self-achievement, and peace and love.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61461016 and 61661012)the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Grant Nos.2014GXNSFAA118366,2014GXNSFAA118283,and 2015jj BB7002)the Innovation Project of Graduate Education of Guilin University of Electronic Technology,China(Grant No.2016YJCX82)
文摘An ultrathin micro-split Jerusalem-cross metasurface is proposed in this paper, which can efficiently convert the linear polarization of electromagnetic （EM） wave into the circular polarization in ultra-wideband. By symmetrically employing two micro-splits on the horizontal arm （in the x direction） of the Jerusalem-cross structure, the bandwidth of the proposed device is significantly extended. Both simulated and experimental results show that the proposed metasurface is able to convert linearly polarized waves into circularly polarized waves in a frequency range from 12.4 GHz to 21 GHz, with an axis ratio better than 1 dB. The simulated results also show that such a broadband and high-performance are maintained over a wide range of incident angle. The presented polarization converter can be used in a number of areas, such as spectroscopy and wireless communications.
基金Project supported by the National Natural Science Foundation of China （Grant Nos. 10775055 and 11105002） and the Open-end Fund of State Key Laboratory of Structural Analysis for Industrial Equipment, China （Grant No. GZ 1215）.
文摘The influence of the gap on the absorption performance of the conventional split ring resonator(SRR) absorber is investigated at microwave frequencies. Our simulated results reveal that the geometry of the square SRR can be equivalent to a Jerusalem cross(JC) resonator and its corresponding metamaterial absorber(MA) is changed to a JC absorber. The JC MA exhibits an experimental absorption peak of 99.1% at 8.72 GHz, which shows an excellent agreement with our simulated results. By simply assembling several JCs with slightly different geometric parameters next to each other into a unit cell, a perfect multi-band absorption can be effectively obtained. The experimental results show that the MA has four distinct and strong absorption peaks at 8.32 GHz, 9.8 GHz, 11.52 GHz and 13.24 GHz. Finally, the multi-reflection interference theory is introduced to interpret the absorption mechanism.
文摘This essay employs the approach of New Criticism close reading to interpret My Jerusalem by a contemporary Chinese poet, Wang Guilin, from the dialogic perspective of＂I and Thou.＂ From a dimension of faith beyond daily life, the poet narrates his astonishment, historical reflection and spiritual transformation during a visit to Jerusalem. For him, the journey to Jerusalem was also a pilgrimage to a spiritual homeland, self-achievement, and peace and love.
