Affiliation: | 1. Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan, USA;2. Research Center for Photovoltaic Technologies, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan;3. Applied Physics Program, University of Michigan, Ann Arbor, Michigan, USA;4. Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan, USA |