Topological nanostructures with halide perovskites Alexander - - PowerPoint PPT Presentation
Topological nanostructures with halide perovskites Alexander Berestennikov berestennikov.alex@gmail.com METANANO 2020 Halide perovskites Simple fabrication Easy processing High refractive index (n = 2-3) Chemically
Alexander Berestennikov berestennikov.alex@gmail.com METANANO 2020
Hasan, Kane. Rev. Mod. Phys. 82, 3045 (2010)
The concept of topological insulators
Periodically stacking materials with different dielectric
“infinite” structure
Joannopoulos, J. D., Johnson, S. G., Winn, J. N. & Meade, R. D., Photonic Crystals: Molding the Flow of Light, 2nd ed. (Princeton University Press, Princeton , 2008)
model 1 2 4 5 6 7
Energy spectrum Field distribution for the edge mode Experimental observation: [1] N. Malkova, et al. Optics Letters, vol. 34, 1633 (2009). [2] Sinev, et al. Nanoscale 7, 11904 (2015). [3] Blanco-Redondo, et al. Phys. Rev. Lett. 116, 163901 (2016).
Realized in electronic, photonic, plasmonic, polaritonic and mechanical systems
Su, Schrieffer, Heeger. Physical Review Letters, 42 (25), P. 1698–1701 (1979)
Non-Hermitian variant of the paradigmatic Su-Schrieffer-Heeger (SSH) model The coupling profile is precisely controlled by the separations between adjacent rings
Han Zhao et al., Nat. Comm. 9, 981 (2018)
708 нм Q = 22 705 нм Q = 21 Thickness: 70 nm +20nm layer (n=2.5) 13 ячеек 701 нм Q = 30
645 nm 635 nm 625 nm 620 nm 615 nm
550 600 650 700 750 800
50 100 150 200 250 300
102 d1-2 big triangle 102 d1-2 center 102 d1-2 corner