在12倍对称的准晶体中完成光子带隙
1Department of Electronics and Computer Science, University of Southampton, UK.
Nature
|April 28, 2000
概括
相比于周期性光子晶体,光子准晶体能够使用小空气孔完成光子带隙. 这一突破允许在具有较低折射率的材料中高效地操纵光线,有望成为先进的光学设备.
科学领域:
- 光子学 是一个光子学.
- 材料科学 材料科学 材料科学
- 光学是什么?光学是什么?光学是什么?
背景情况:
- 光子晶体利用光子带隙通过在周期结构中散射光子来控制光的传播.
- 传统的光子晶体在高折射率材料中需要大气孔来完成带隙,从而限制光学传输.
- 介电板波导中的周期格子可以表现出光子带隙,但对孔尺寸和材料选择有局限性.
研究的目的:
- 通过实验证明准晶格子可以拥有光子带隙.
- 研究在具有较小空气孔的光子准晶体中实现完整的光子带隙.
- 探索光子准晶体在光学设备中的潜力,使用具有较低折射率的材料.
主要方法:
- 在介电板波导中的垂直空气孔的二维半晶格子的制造.
- 对光子带隙性质的实验性表征,包括非定向和偏振独立的行为.
- 利用化 (n = 2.02) 和玻璃 (n = 1.45) 等材料用于光子准晶体制造.
主要成果:
- 在准晶格子中成功实验证明了光子带隙.
- 在化和玻璃中实现了完整的光子带隙,具有小的空气孔.
- 实现了非定向和偏振独立的光子带隙,克服了周期结构的局限性.
结论:
- 光子半晶体为周期性光子晶体提供了可行的替代方案,以实现完整的光子带隙.
- 在较低折射率材料中使用小型空气孔在准晶体设计中是可行的.
- 光子准晶体在开发具有更高性能和兼容性的先进光学设备方面显示出重大前景.
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