Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/341230
Type: Artigo
Title: Dipole modelling for a robust description of subdiffractional polariton waves
Author: Feres, F. H.
Barcelos, I. D.
Mayer, R. A.
Santos, T. M. dos
Freitas, R. O.
Raschke, M. B.
Bahamon, D. A.
Maia, F. C. B.
Abstract: The nanophotonics of van der Waals (vdW) materials relies critically on the electromagnetic properties of polaritons defined on sub-diffraction length scales. Here, we use a full electromagnetic Hertzian dipole antenna (HDA) model to describe the hyperbolic phonon polaritons (HP(2)s) in vdW crystals of hexagonal boron nitride (hBN) on a gold surface. The HP2 waves are investigated by broadband synchrotron infrared nanospectroscopy (SINS) which covers the type I and type II hyperbolic bands simultaneously. Basically, polariton waves, observed by SINS, are assigned to the resultant electric field from the summation over the irradiated electric fields of dipoles distributed along the crystal edge and at the tip location and a non-propagating field. The values of polariton momenta and damping extracted from the HDA model present excellent agreement with theoretical predictions. Our analysis shows that the confinement factor of type I HP(2)s exceeds that of the type II ones by up to a factor of 3. We extract anti-parallel group velocities (v(g)) for type I (v(g,typeI) = -0.005c, c is the light velocity in a vacuum) in relation to type II (v(g,typeII) = 0.05c) polaritonic pulses, with lifetimes of similar to 0.6 ps and similar to 0.3 ps, respectively. Furthermore, by incorporating consolidated optical-near field theory into the HDA model, we simulate real-space images of polaritonic standing waves for hBN crystals of different shapes. This approach reproduces the experiments with a minimal computational cost. Thus, it is demonstrated that the HDA modelling self-consistently explains the measured complex-valued polariton near-field, while being a general approach applicable to other polariton types, like plasmon- and exciton-polaritons, active in the wide range of vdW materials.
Subject: Polaritons
Nitreto de boro hexagonal
Fônons
Polaritons
Hexagonal boron nitride
Phonons
Country: Reino Unido
Editor: Royal Society of Chemistry
Rights: fechado
Identifier DOI: 10.1039/c9nr07387f
Address: https://pubs.rsc.org/en/content/articlelanding/2019/NR/C9NR07387F
Date Issue: 2019
Appears in Collections:IFGW - Artigos e Outros Documentos

Files in This Item:
File SizeFormat 
000503282100015.pdf2.75 MBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.