1. Department of Mechanical Engineering; Massachusetts Institute of Technology; 77 Massachusetts Ave Cambridge MA 02139 USA
2. Micro and Nanotechnology Programme; The Center for Solar Energy Research and Applications; Department of Electrical and Electronics Engineering; Middle East Technical University; Dumlupinar Blv, No. 1 06800 Cankaya Ankara Turkey
3. Department of Mechanical Engineering; The University of Auckland; Auckland New Zealand
4. Department of Chemical and Biological Engineering; The University of New Mexico; 1 University of New Mexico Albuquerque NM 87131 USA
5. Electrical and Computer Engineering Department; The University of North Carolina at Charlotte; Charlotte NC 28223 USA