title: Experimental Demonstration of Effective Medium Approximation Breakdown in Deeply Subwavelength All-Dielectric Multilayers.
abstract: We report the first experimental demonstration of anomalous breakdown of the effective medium approximation in all-dielectric deeply subwavelength thickness (d∼λ/160-λ/30) multilayers, as recently predicted theoretically [H. H. Sheinfux et al., Phys. Rev. Lett. 113, 243901 (2014)]. Multilayer stacks are composed of alternating alumina and titania layers fabricated using atomic layer deposition. For light incident on such multilayers at angles near the total internal reflection, we observe pronounced differences in the reflectance spectra for structures with 10- vs 20-nm thick layers, as well as for structures with different layers ordering, contrary to the predictions of the effective medium approximation. The reflectance difference can reach values up to 0.5, owing to the chosen geometrical configuration with an additional resonator layer employed for the enhancement of the effect. Our results are important for the development of new high-precision multilayer ellipsometry methods and schemes, as well as in a broad range of sensing applications.
authors.affiliation: DTU Fotonik-Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads 343, DK-2800 Kgs. Lyngby, Denmark.|ITMO University, Kronverksky pr. 49, St. Petersburg, 197101, Russia.
authors.forename: Sergei V
authors.initials: SV
authors.lastname: Zhukovsky
authors.affiliation: DTU Fotonik-Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads 343, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Andrei
authors.initials: A
authors.lastname: Andryieuski
authors.affiliation: DTU Fotonik-Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads 343, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Osamu
authors.initials: O
authors.lastname: Takayama
authors.affiliation: DTU Fotonik-Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads 343, DK-2800 Kgs. Lyngby, Denmark.|DTU Danchip-National Center for Micro- and Nanofabrication, Technical University of Denmark, Ørsteds Plads 347, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Evgeniy
authors.initials: E
authors.lastname: Shkondin
authors.affiliation: DTU Fotonik-Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads 343, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Radu
authors.initials: R
authors.lastname: Malureanu
authors.affiliation: DTU Danchip-National Center for Micro- and Nanofabrication, Technical University of Denmark, Ørsteds Plads 347, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Flemming
authors.initials: F
authors.lastname: Jensen
authors.affiliation: DTU Fotonik-Department of Photonics Engineering, Technical University of Denmark, Ørsteds Plads 343, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Lavrinenko