1. Center for Organic Photonics and Electronics (COPE), School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
2. Department of Electrical Engineering, Princeton University, Princeton, NJ 08544, USA.
3. Center for Organic Photonics and Electronics (COPE), School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA.
4. Solvay SA, rue de Ransbeek 310, 1120 Brussels, Belgium.
5. Center for Organic Photonics and Electronics (COPE), George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.