Microwave seminar | 03 July 2023

Nanoantennas working at optical frequencies is an interesing branch of the present research worldwide. As well as nanofabrication techniques are being improved, potential applications might become a reality [1, 2]. Here, plasmonic nanoantennas with constant input impedance within a wide range of mid infrared frequencies are designed. For antennas working in lower frequencies like radiofrequencies or microwaves, it could be done by using self-complementary geometries as long as the Babinet’s principle is approximately valid [3]. However, the scaling up to the infrared is not trivial since metals are not good conductors in such high frequencies. We have found an alternative way to recover the validity of the Babinet’s principle and thus the achievement of constant input impedance [4].

Main paper/arXiv, related to the seminar, and other references

[1] V. Giannini, A. I. Fernández-Domínguez, S. C. Heck, and S. A. Maier, “Plasmonic Nanoantennas: Fundamentals and Their Use in Controlling the Radiative Properties of Nanoemitters,” Chem. Rev., vol. 111, pp. 3888-3912, 2011.
[2] P. Biagioni, J.-S. Huang, and B. Hecht, “Nanoantennas for visible and infrared radiation,” Rep. Prog. Phys., vol. 75, p. 024402, 2012.
[3] Y. Mushiake, Self-complementary antennas: principle of self-complementarity for constant impedance, Springer, 1966.
[4] J. D. Ortiz, J. P. del Risco, J. D. Baena, R. Marqués, “Extension of Babinet's principle for plasmonic metasurfaces,” Appl. Phys. Lett., vol. 119, p. 161103 (2021). Supplementary material: https://aip.scitation.org/doi/suppl/10.1063/5.0065724.