Theoretical seminar | 04 December 2024

Surface plasmons in metal-dielectric interfaces attract interest as an efficient mechanism to spatial confinement of light. Usually, surface plasmons are bound to two-dimensional (2D) metal-dielectric interfaces. Moreover, for coplanar 2D materials, it has been theoretically shown a one-dimensional (1D) metal-dielectric interface can support a 1D plasmon effectively guiding energy along a line [1]. It has been also shown that this mode occurs when the boundary separates 2D materials with complementary surface impedances [2, 3]. In fact, it is possible to control the wave confinement by altering both surface impedances correspondingly. First experimental demonstrations of this type of 1D waves have been provided in microwaves by using two metal screens exhibiting complementary patterns. For instance, an array of metallic patches and its complementary grid. In such a demonstration, metal is not considered as a plasmonic material but a good conductor. When one tries to scale down the geometry to push up the working frequency, one finds the next issue: Babinet's principle is not rigorously valid for plasmonic metasurfaces [4] mainly because metals are no longer good conductors, and so the geometry must
be rethought. Recently, we propose a new way to circumvent this issue and designed a boundary between two complementary plasmonic metasurfaces able to hold 1D plasmons [5].

Main paper/arXiv, related to the seminar, and other references, up to 5
[1] D. R. Mason, S. G. Menabde, S. Yu, and N. Park, “Plasmonic Excitations of 1D Metal-Dielectric Interfaces in 2D Systems: 1D Surface Plasmon Polaritons,” Sci. Rep. 4, 4536 (2014).
[2] D. J. Bisharat, D. F. Sievenpiper, “Guiding Waves Along an Infinitesimal Line between Impedance Surfaces,” Phys. Rev. Lett. 119, 106802 (2017).
[3] X. Kong, D. J. Bisharat, G. Xiao, D. F. Sievenpiper, “Analytic theory of an edge mode between impedance surfaces,” Phys. Rev. A 99, 033842 (2019).
[4] J. D. Ortiz et al., “Extension of Babinet's principle for plasmonic metasurfaces,” Appl. Phys. Lett. 119, 161103 (2021).
[5] J. D. Baena, A. C. Escobar, J. P. del Risco and R. Marqués, "Guiding Line Plasmons Between Complementary Plasmonic Metasurfaces," 2022 Sixteenth International Congress on Artificial Materials for Novel Wave Phenomena (Metamaterials), Siena, Italy, 2022, pp. X-037-X-039, doi: 10.1109/Metamaterials54993.2022.9920918.