Open AccessStrong coupling of Bloch surface waves and excitons in ZnO up to 430 K
Author(s) -
Sebastian Henn,
Marius Grundmann,
Chris Sturm
Publication year - 2021
Publication title -
new journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.584
H-Index - 190
ISSN - 1367-2630
DOI - 10.1088/1367-2630/ac2452
Subject(s) - polariton , physics , exciton , surface phonon , distributed bragg reflector , resonance (particle physics) , condensed matter physics , prism , transverse plane , atomic physics , optics , molecular physics , laser , phonon , structural engineering , engineering
We report on the investigation and observation of Bloch surface wave polaritons, resulting from the interaction between excitons in ZnO and a Bloch surface wave supported by a distributed Bragg reflector (DBR), for temperatures up to 430 K. The samples were fabricated using pulsed laser deposition and consist of a DBR made of 6.5 layer pairs of yttrica-stabilized zirconia and Al 2 O 3 with a ZnO surface layer. We measured the reflectivity of transverse electric modes using a SiO 2 prism in Kretschmann–Raether configuration, giving access to high in-plane momenta. Whereas the lower polariton branch was clearly observable, the upper polariton branch was not visible, due to the strong absorption in ZnO above the excitonic resonance. By employing a coupled oscillator model for the interaction between the bare surface mode and exciton, we derived a corresponding Rabi splitting between 100–192 meV at 294 K, which decreases with increasing temperature.