Coherent terahertz emission from free-electron-driven Fabry-Perot resonators with coupled grooves
Coherent terahertz emission from free-electron-driven Fabry-Perot resonators with coupled grooves
复制标题
具有耦合凹槽的自由电子驱动法布里-珀罗谐振器的相干太赫兹发射
DOI：
10.1088/1361-6463/abc0c1
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Wenxin Liu
中科院分区：
文献类型：
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作者：
Weihao Liu;Liwen Zhang;Zijia Yu;Yucheng Liu;Weiwei Li;Qika Jia;Baogen Sun;Hongliang Xu;Wenxin Liu
具有金属亚波长槽或孔的法布里-珀罗（FP）谐振腔在光学领域有着广泛的应用，近年来在太赫兹波的产生和操控方面引起了越来越多的关注。然而，这种谐振器在太赫兹区域中的实践受到低能量容量和制造高纵横比凹槽/孔的困难的极大限制。在这里，我们说明了一种太赫兹FP谐振器形成的一组耦合槽具有低的纵横比，它具有更高的能量容量，更高的品质因数，比一个单独的非耦合槽形成的更容易制造。利用自由电子束激励FP谐振器阵列，可以实现相干太赫兹辐射，其强度比非耦合槽阵列高出一个数量级以上，为高功率相干太赫兹波的产生提供了一种很有前途的方法。
Fabry–Pérot (FP) resonators with metallic subwavelength grooves or holes, which have been extensively applied in optical region, have recently attracted increasing interest for terahertz wave generation and manipulation. However, the practices of such resonators in the terahertz region are greatly restricted by the low energy-capacity and by the difficulty of manufacturing high-aspect-ratio grooves/holes. Here we illustrate a kind of terahertz FP resonator formed by a cluster of coupled grooves with low-aspect-ratio, which has much higher energy-capacity, higher quality-factor and is much easier to fabricate than one formed by a single uncoupled-groove. Using free-electron beams to excite an array of such FP resonators, coherent terahertz emission can be achieved, the intensity of which is more than an order of magnitude higher than that from an array of uncoupled-grooves, affording a promising way for high-power and coherent terahertz wave generation.