1. Institute for Biomedical Engineering; ETH Zurich; 8092 Zurich Switzerland
2. Laboratory of Organic Electronics; Department of Science and Technology; Linköping University; 601 74 Norrköping Sweden
3. Department of Electrical Engineering; Columbia University; New York NY 10027 USA
4. NYU Neuroscience Institute; School of Medicine; New York University; New York NY 10016 USA