1. Jack
Baskin School of Engineering, University of California at Santa Cruz, Santa
Cruz, California 95064, United States
2. Nanostructured
Energy Conversion Technology and Research (NECTAR), Advanced Studies
Laboratories, NASA Ames Research Center, Moffett
Field, California 94035, United States
3. Department of Electrical & Computer Engineering, University of California at Davis, One Shields Avenue, Davis, California 95616, United States
4. Department
of Electrical Engineering and Electronics, College of Science and
Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara-shi, Kanagawa 252-5258, Japan