通过热的迪拉克子在石墨烯中产生极高效的特拉赫兹高波
Hassan A Hafez1,2,3, Sergey Kovalev4, Jan-Christoph Deinert4
1Fakultät für Physik, Universität Duisburg-Essen, Duisburg, Germany.
Nature
|September 12, 2018
概括
研究人员在室温下在单层石墨烯中证明了高效的太赫兹波生成. 在非线性光学领域的这一突破使得使用石墨烯电子技术实现高频信号转换.
科学领域:
- 非线性光学
- 凝聚物质物理学
- 材料科学
背景情况:
- 多重光生成对于电子和光电子中的频率转换和生成至关重要.
- 石墨烯的独特电子带结构与无质的迪拉克费米子表明了太赫兹波生成的高效率,但实验证实还不够.
研究的目的:
- 在单层石墨烯中实验证实和证明高效的太赫兹波生成.
- 研究石墨烯在太赫兹频率合成中的潜力.
主要方法:
- 在单层石墨烯中生成到第七阶的太赫兹波.
- 在室温和环境条件下使用低强度的特拉赫兹场 (几十kV/cm).
- 在时间域中直接观察太赫兹波.
主要成果:
- 在单层石墨烯中实现到第七阶的太赫兹波生成.
- 观察到高场转换效率分别超过10−3,10−4和10−5.
- 石墨烯对这些波的非线性光学系数比典型的固体高7-18个数量级.
结论:
- 在石墨烯中迪拉克电子的集体热反应是高效的太赫兹波生成的关键.
- 使用当前的石墨烯电子, 提供高效的太赫兹频率合成的直接途径.
- 证明了石墨烯在需要高频信号生成的先进光电子应用中的潜力.
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