1. Institute for Solar Energy Research Hamelin (ISFH)Am Ohrberg 131860 EmmerthalGermany
2. Department of Solar EnergyInstitute of Solid‐State PhysicsLeibniz University HannoverAppelstraße 230167 HannoverGermany
3. Helmholtz‐Zentrum Dresden‐RossendorfInstitute of Ion Beam Physics and Materials ResearchBautzner Landstraße 40001328 DresdenGermany