1 Department of Physics and Astronomy, University of Alabama, Tuscaloosa, 35487 Alabama, USA.
2 Department of Physics, Federal University of Ceara, Fortaleza, 60455-760 Ceara, Brazil.
3 Department of Polymer Engineering, School of Polymer Science and Engineering, and Alan G. MacDiarmid Energy Research Institute, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea.
4 Research Institute for Supra-Materials, Shinshu University, 4-17-1 Wakasato, 380-8553 Nagano, Japan.
5 Institute of Natural Sciences, Graduate Program in Physics, Federal University of Para, Belem 66075-110, Brazil.
6 Department of Physics, Massachusetts Institute of Technology, Cambridge 02139, Massachusetts, USA.
7 Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge 02139, Massachusetts, USA.