来自等离子体元表面的巨大非线性响应与子带间过渡相结合
Jongwon Lee1, Mykhailo Tymchenko1, Christos Argyropoulos1
1Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
Nature
|July 4, 2014
概括
研究人员通过将电磁模式与半导体异构结构相合,开发出了新的等离子金属表面. 这一突破为先进的光学设备实现了创纪录的高非线性光学响应.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 非线性光学是一种非线性光学.
- 塑制剂是一种塑制剂.
- 半导体异构结构中的半导体.
背景情况:
- 半导体异构结构中的子带间过渡提供了很大的非线性光学响应,但仅限于特定的光极化.
- 等离子元表面增强了光物质相互作用,并使具有独特波特性的超薄设备成为可能.
研究的目的:
- 提出并实验实现具有显著增强非线性光学响应的超表面.
- 为了利用等离子体元表面和量子工程电子间子带过渡之间的合.
- 为实现多功能光学功能设计非线性灵敏度张量.
主要方法:
- 制造超薄 (400nm) 超表面,结合等离子体和半导体异构结构组件.
- 实验验证增强的非线性光学特性,特别是第二波代 (SHG).
- 在约8微米波长的正常发作下非线性易感度张量的表征.
主要成果:
- 实现了创纪录的非线性易感度,超过5 × 10^4 pm/V的SHG,数量级大于以前的光学元表面.
- 证明了设计非线性易感度张量器的各种元素的能力.
- 证实了高效的频率混合和宽带频率转换,相和全光学控制的潜力.
结论:
- 拟议的超表面代表了非线性光学的重大进步,提供超薄,高效的光学元素.
- 这项技术可以在频率转换和全光信号处理方面实现实际应用,并且相匹配要求放松.
- 工程合为平面设备中的非线性光学响应提供了前所未有的控制.
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