1st Institute of Physics (IA), RWTH Aachen University, 52056 Aachen, Germany.
ACS Nano. 2012 Nov 27;6(11):10107-14. doi: 10.1021/nn303845a. Epub 2012 Oct 19.
Graphene as a one-atom-thick planar sheet can support surface plasmons at infrared (IR) and terahertz (THz) frequencies, opening up exciting possibilities for the emerging research field of graphene plasmonics. Here, we theoretically report that a layered graphene-lens (GL) enables the enhancement of evanescent waves for near-field subdiffractive imaging. Compared to other resonant imaging devices like superlenses, the nonresonant operation of the GL provides the advantages of a broad intrinsic bandwidth and a low sensitivity to losses, while still maintaining a good subwavelength resolution of better than λ/10. Most importantly, thanks to the large tunability of the graphene, we show that our GL is a continuously frequency-tunable subwavelength-imaging device in the IR and THz regions, thus allowing for ultrabroadband spectral applications.
石墨烯是一种只有一个原子厚的平面薄片，可以支持红外（IR）和太赫兹（THz）频率的表面等离激元，为新兴的石墨烯等离激元学研究领域开辟了令人兴奋的可能性。在这里，我们从理论上报告了分层石墨烯透镜（GL）能够增强近场亚衍射成像的消逝波。与超透镜等其他共振成像设备相比，GL 的非共振操作具有固有带宽宽和对损耗不敏感的优点，同时仍然保持了优于 λ/10 的良好亚波长分辨率。最重要的是，由于石墨烯的高可调节性，我们表明我们的 GL 是一个在 IR 和 THz 区域中连续频率可调的亚波长成像设备，从而允许进行超宽带光谱应用。
