Divergence of the dielectric constant in ultrathin granular metal films near the percolation threshold
We report on the electronic and optical properties of ultrathin granular films. We demonstrate that the static dielectric constant increases with thickness in the dielectric regime and diverges at the critical thickness, as predicted by classical percolation theory. However, for thicker samples, the...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2020-01-01
|
| Series: | New Journal of Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1367-2630/aba021 |
| _version_ | 1797750432722845696 |
|---|---|
| author | H Bakkali E Blanco S E Lofland M Domínguez |
| author_facet | H Bakkali E Blanco S E Lofland M Domínguez |
| author_sort | H Bakkali |
| collection | DOAJ |
| description | We report on the electronic and optical properties of ultrathin granular films. We demonstrate that the static dielectric constant increases with thickness in the dielectric regime and diverges at the critical thickness, as predicted by classical percolation theory. However, for thicker samples, the dc conductivity does not obey scaling laws due to the presence of tunneling conduction. In this region the dielectric constant is positive, and the electronic transport is not metallic but can be described by Jonscher’s universal power law, even though there is a Drude-like response indicating the presence of free charge carriers. Only for thicker films when the dielectric constant becomes negative is there metallic conduction. |
| first_indexed | 2024-03-12T16:32:36Z |
| format | Article |
| id | doaj.art-9814c1c3dad04572b015aac5f3a5b567 |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:32:36Z |
| publishDate | 2020-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-9814c1c3dad04572b015aac5f3a5b5672023-08-08T15:25:23ZengIOP PublishingNew Journal of Physics1367-26302020-01-0122808301810.1088/1367-2630/aba021Divergence of the dielectric constant in ultrathin granular metal films near the percolation thresholdH Bakkali0https://orcid.org/0000-0001-7351-3948E Blanco1https://orcid.org/0000-0002-2234-1477S E Lofland2https://orcid.org/0000-0002-1024-5103M Domínguez3https://orcid.org/0000-0002-7889-7220Department of Physics and Astronomy, Rowan University , 201 Mullica Hill Road, Glassboro, NJ 08028, United States of America; Departamento de Física de la Materia Condensada & IMEYMAT: Institute of Research on Electron Microscopy and Materials, University of Cadiz , E11510 Puerto Real, Cádiz, SpainDepartamento de Física de la Materia Condensada & IMEYMAT: Institute of Research on Electron Microscopy and Materials, University of Cadiz , E11510 Puerto Real, Cádiz, SpainDepartment of Physics and Astronomy, Rowan University , 201 Mullica Hill Road, Glassboro, NJ 08028, United States of AmericaDepartamento de Física de la Materia Condensada & IMEYMAT: Institute of Research on Electron Microscopy and Materials, University of Cadiz , E11510 Puerto Real, Cádiz, SpainWe report on the electronic and optical properties of ultrathin granular films. We demonstrate that the static dielectric constant increases with thickness in the dielectric regime and diverges at the critical thickness, as predicted by classical percolation theory. However, for thicker samples, the dc conductivity does not obey scaling laws due to the presence of tunneling conduction. In this region the dielectric constant is positive, and the electronic transport is not metallic but can be described by Jonscher’s universal power law, even though there is a Drude-like response indicating the presence of free charge carriers. Only for thicker films when the dielectric constant becomes negative is there metallic conduction.https://doi.org/10.1088/1367-2630/aba021percolationtunneling conductionoptical conductivity |
| spellingShingle | H Bakkali E Blanco S E Lofland M Domínguez Divergence of the dielectric constant in ultrathin granular metal films near the percolation threshold New Journal of Physics percolation tunneling conduction optical conductivity |
| title | Divergence of the dielectric constant in ultrathin granular metal films near the percolation threshold |
| title_full | Divergence of the dielectric constant in ultrathin granular metal films near the percolation threshold |
| title_fullStr | Divergence of the dielectric constant in ultrathin granular metal films near the percolation threshold |
| title_full_unstemmed | Divergence of the dielectric constant in ultrathin granular metal films near the percolation threshold |
| title_short | Divergence of the dielectric constant in ultrathin granular metal films near the percolation threshold |
| title_sort | divergence of the dielectric constant in ultrathin granular metal films near the percolation threshold |
| topic | percolation tunneling conduction optical conductivity |
| url | https://doi.org/10.1088/1367-2630/aba021 |
| work_keys_str_mv | AT hbakkali divergenceofthedielectricconstantinultrathingranularmetalfilmsnearthepercolationthreshold AT eblanco divergenceofthedielectricconstantinultrathingranularmetalfilmsnearthepercolationthreshold AT selofland divergenceofthedielectricconstantinultrathingranularmetalfilmsnearthepercolationthreshold AT mdominguez divergenceofthedielectricconstantinultrathingranularmetalfilmsnearthepercolationthreshold |