[1] Gdansk Univ Technol, Dept Solid State Phys, Fac Appl Phys & Math, Ul Narutowicza 11-12, PL-80233 Gdansk, Poland
[2] Univ Oslo, FERMiO, Ctr Mat Sci & Nanotechnol, Dept Chem, Gaustadalleen 21, NO-0349 Oslo, Norway
[3] SINTEF Mat & Chem, POB 124 Blindern, NO-0314 Oslo, Norway