Strategies to enhance THz harmonic generation combining multilayered, gated, and metamaterialbased architectures  

作　　者：Ali Maleki Moritz B.Heindi Yongbao Xin Robert W.Boyd Georg Herink Jean-Michel Menard 

机构地区：[1]Department of Physics,University of Ottawa,Ottawa,ON K1N 6N5,Canada [2]Experimental Physics VIl-Ultrafast Dynamics,University of Bayreuth,Bayreuth95447,Germany [3]iridian Spectral Technologies Ltd,Ottawa,ON K1G 6R8,Canada [4]School of Electrical Engineering and Computer Science,University of Ottawa,Ottawa,ON K1N 6N5,Canada [5]institute of Optics and Department of Physics and Astronomy,University of Rochester,Rochester,NY 14627,USA

出　　处：《Light(Science & Applications)》2025年第2期356-365,共10页光(科学与应用)(英文版)

基　　金：funding from the Natural Sciences and Engineering Research Council of Canada(NSERC)Discovery funding program(RGPIN-2023-05365);the University of Bayreuth Centre of International Excellence"Alexander von Humboldt".G.H.acknowledges funding by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation),via project 492723217.A.Maleki,G.Herink and J.-M.Menard acknowledge financial support from the Mitacs Globalink Research Award.

摘　　要：Graphene has unique properties paving the way for groundbreaking future applications.Its large optical nonlinearity and ease of integration in devices notably makes it an ideal candidate to become a key component for all-optical switching and frequency conversion applications.In the terahertz(THz)region,various approaches have been independently demonstrated to optimize the nonlinear effects in graphene,addressing a critical limitation arising from the atomically thin interaction length.Here,we demonstrate sample architectures that combine strategies to enhance THz nonlinearities in graphene-based structures.We achieve this by increasing the interaction length through a multilayered design,controlling carrier density with an electrical gate,and modulating the THz field spatial distribution with a metallic metasurface substrate.Our study specifically investigates third harmonic generation(THG)using a table-top high-field THz source.We measure THG enhancement factors exceeding thirty and propose architectures capable of achieving a two-order-of-magnitude increase.These findings underscore the potential of engineered graphene-based structures in advancing THz frequency conversion technologies for signal processing and wireless communication applications.

关 键 词：harmonic generation optimize nonlinear effects graphene terahertz third harmonic generation multilayered architecture METAMATERIAL nonlinear effects 

分 类 号：O441.4[理学—电磁学]