Dr. Lutz Geelhaar Head of Department Epitaxy +49 30 20377-359 geelhaar@pdi-berlin.de Epitaxy Room: 714 Core research areas III-V Nanowires for Optoelectronics , Intersubband Emitters: GaAs-based Quantum-Cascade Lasers Projects Lead-free piezoelectric nanowire-nanocellulose hybrids for flexible energy harvesters (Nanoflex)