1. School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, United Kingdom
2. CIC nanoGUNE BRTA, Tolosa Hiribidea, 76, 20018 Donostia-San Sebastián, Basque Country, Spain
3. Experimentelle Physik 2, Technische Universität Dortmund, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
4. Laboratoire d’Acoustique de l’Uiversité du Mans (LAUM), UMR 6613, Institut d’Acoustique - Graduate School (IA-GS), CNRS, Le Mans Université, 72085 Le Mans, France
5. IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Basque Country Spain
6. Department of Theoretical Physics, V.E. Lashkaryov Institute of Semiconductor Physics, Pr. Nauky 41, 03028 Kyiv, Ukraine
7. Raith GmbH, Konrad-Adenauer-Allee 8, 44263 Dortmund, Germany