Author Affiliations

Kalle Koskinen,^*,1 Sergey Scherbak,^2,3 Semyon Chervinskii,^2,4 Andrey Lipovskii,^2,3 and Martti Kauranen¹

¹Laboratory of Photonics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland

²Institute of Physics, Nanotechnology and Telecommunication, Peter the Great St. Petersburg Polytechnic University, Polytechnicheskaya 29, St. Petersburg, 195251 Russia

³Department of Physics and Technology of Nanostructures, St. Petersburg Academic University, Khlopina 8/3, St. Petersburg, 194021 Russia

⁴Institute of Photonics, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland

^*Corresponding author: kalle.o.koskinen@tut.fi