1. Materials Department, University of California, Santa Barbara, California 93106, USA
2. Institute of Photonics and Nanotechnology, Vilnius University, Sauletekio 3, 10257 Vilnius, Lithuania
3. Laboratoire de Physique de la Matière Condensée, CNRS-Ecole Polytechnique, Université Paris-Saclay, 91128 Palaiseau Cedex, France