Extracting the infrared permittivity of SiO2 substrates locally by near-field imaging of phonon polaritons in a van der Waals crystal

article Extracting the infrared permittivity of SiO2 substrates locally by near-field imaging of phonon polaritons in a van der Waals crystal published yes Patricia Aguilar-Merino author Gonzalo Álvarez-Pérez author Javier Taboada-Gutiérrez author Jiahua Duan author Ivan Prieto Gonzalez author 2A307FE2-F248-11E8-B48F-1D18A9856A870000-0002-7370-5357 Luis Manuel Álvarez-Prado author Alexey Y. Nikitin author Javier Martín-Sánchez author Pablo Alonso-González author NanoFab department Layered materials in which individual atomic layers are bonded by weak van der Waals forces (vdW materials) constitute one of the most prominent platforms for materials research. Particularly, polar vdW crystals, such as hexagonal boron nitride (h-BN), alpha-molybdenum trioxide (α-MoO3) or alpha-vanadium pentoxide (α-V2O5), have received significant attention in nano-optics, since they support phonon polaritons (PhPs)―light coupled to lattice vibrations― with strong electromagnetic confinement and low optical losses. Recently, correlative far- and near-field studies of α-MoO3 have been demonstrated as an effective strategy to accurately extract the permittivity of this material. Here, we use this accurately characterized and low-loss polaritonic material to sense its local dielectric environment, namely silica (SiO2), one of the most widespread substrates in nanotechnology. By studying the propagation of PhPs on α-MoO3 flakes with different thicknesses laying on SiO2 substrates via near-field microscopy (s-SNOM), we extract locally the infrared permittivity of SiO2. Our work reveals PhPs nanoimaging as a versatile method for the quantitative characterization of the local optical properties of dielectric substrates, crucial for understanding and predicting the response of nanomaterials and for the future scalability of integrated nanophotonic devices. https://research-explorer.ista.ac.at/download/9038/9042/2020_Nanomaterials_Aguilar_Merino.pdf application/pdfno MDPI2021 eng Nanomaterials 20794991 33430225 00061063660000110.3390/nano11010120 111 P. Aguilar-Merino, G. Álvarez-Pérez, J. Taboada-Gutiérrez, J. Duan, I. Prieto Gonzalez, L.M. Álvarez-Prado, A.Y. Nikitin, J. Martín-Sánchez, P. Alonso-González, Nanomaterials 11 (2021). Aguilar-Merino, Patricia, et al. “Extracting the Infrared Permittivity of SiO2 Substrates Locally by Near-Field Imaging of Phonon Polaritons in a van Der Waals Crystal.” Nanomaterials, vol. 11, no. 1, 120, MDPI, 2021, doi:<a href="https://doi.org/10.3390/nano11010120">10.3390/nano11010120</a>. Aguilar-Merino P, Álvarez-Pérez G, Taboada-Gutiérrez J, Duan J, Prieto Gonzalez I, Álvarez-Prado LM, Nikitin AY, Martín-Sánchez J, Alonso-González P. 2021. Extracting the infrared permittivity of SiO2 substrates locally by near-field imaging of phonon polaritons in a van der Waals crystal. Nanomaterials. 11(1), 120. Aguilar-Merino, P., Álvarez-Pérez, G., Taboada-Gutiérrez, J., Duan, J., Prieto Gonzalez, I., Álvarez-Prado, L. M., … Alonso-González, P. (2021). Extracting the infrared permittivity of SiO2 substrates locally by near-field imaging of phonon polaritons in a van der Waals crystal. Nanomaterials. MDPI. <a href="https://doi.org/10.3390/nano11010120">https://doi.org/10.3390/nano11010120</a> P. Aguilar-Merino et al., “Extracting the infrared permittivity of SiO2 substrates locally by near-field imaging of phonon polaritons in a van der Waals crystal,” Nanomaterials, vol. 11, no. 1. MDPI, 2021. Aguilar-Merino, Patricia, Gonzalo Álvarez-Pérez, Javier Taboada-Gutiérrez, Jiahua Duan, Ivan Prieto Gonzalez, Luis Manuel Álvarez-Prado, Alexey Y. Nikitin, Javier Martín-Sánchez, and Pablo Alonso-González. “Extracting the Infrared Permittivity of SiO2 Substrates Locally by Near-Field Imaging of Phonon Polaritons in a van Der Waals Crystal.” Nanomaterials. MDPI, 2021. <a href="https://doi.org/10.3390/nano11010120">https://doi.org/10.3390/nano11010120</a>. Aguilar-Merino P, Álvarez-Pérez G, Taboada-Gutiérrez J, et al. Extracting the infrared permittivity of SiO2 substrates locally by near-field imaging of phonon polaritons in a van der Waals crystal. Nanomaterials. 2021;11(1). doi:<a href="https://doi.org/10.3390/nano11010120">10.3390/nano11010120</a> 90382021-01-24T23:01:09Z2023-08-07T13:35:50Z