Observation of the universal magnetoelectric effect in a 3D topological insulator
Zitieren Sie bitte immer diese URN: urn:nbn:de:bvb:20-opus-170875
- The electrodynamics of topological insulators (TIs) is described by modified Maxwell’s equations, which contain additional terms that couple an electric field to a magnetization and a magnetic field to a polarization of the medium, such that the coupling coefficient is quantized in odd multiples of α/4π per surface. Here we report on the observation of this so-called topological magnetoelectric effect. We use monochromatic terahertz (THz) spectroscopy of TI structures equipped with a semitransparent gate to selectively address surface states.The electrodynamics of topological insulators (TIs) is described by modified Maxwell’s equations, which contain additional terms that couple an electric field to a magnetization and a magnetic field to a polarization of the medium, such that the coupling coefficient is quantized in odd multiples of α/4π per surface. Here we report on the observation of this so-called topological magnetoelectric effect. We use monochromatic terahertz (THz) spectroscopy of TI structures equipped with a semitransparent gate to selectively address surface states. In high external magnetic fields, we observe a universal Faraday rotation angle equal to the fine structure constant α=e\(^{2}\)/2E\(_{0}\)hc (in SI units) when a linearly polarized THz radiation of a certain frequency passes through the two surfaces of a strained HgTe 3D TI. These experiments give insight into axion electrodynamics of TIs and may potentially be used for a metrological definition of the three basic physical constants.…
Autor(en): | V. Dziom, A. Shuvaev, A. Pimenov, G.V. Astakhov, C. Ames, K. Bendias, J. Böttcher, G. Tkachov, E.M. Hankiewicz, C. Brüne, H. Buhmann, L.W. Molenkamp |
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URN: | urn:nbn:de:bvb:20-opus-170875 |
Dokumentart: | Artikel / Aufsatz in einer Zeitschrift |
Institute der Universität: | Fakultät für Physik und Astronomie / Physikalisches Institut |
Fakultät für Physik und Astronomie / Institut für Theoretische Physik und Astrophysik | |
Sprache der Veröffentlichung: | Englisch |
Titel des übergeordneten Werkes / der Zeitschrift (Englisch): | Nature Communications |
Erscheinungsjahr: | 2017 |
Band / Jahrgang: | 8 |
Heft / Ausgabe: | 15197 |
Originalveröffentlichung / Quelle: | Nature Communications 2017, 8:15197. DOI: 10.1038/ncomms15197 |
DOI: | https://doi.org/10.1038/ncomms15197 |
PubMed-ID: | https://pubmed.ncbi.nlm.nih.gov/28504268 |
Allgemeine fachliche Zuordnung (DDC-Klassifikation): | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
Freie Schlagwort(e): | infrared spectroscopy; topological insulators; topological magnetoelectric effect; topological matter |
Datum der Freischaltung: | 14.10.2019 |
Lizenz (Deutsch): | CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International |