1. School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, Arizona 85287, USA
2. National Renewable Energy Laboratory, Golden, Colorado 80401, USA
3. Mechanical Engineering Department, Colorado State University, Fort Collins, Colorado 80523, USA
4. Loughborough University, Loughborough, United Kingdom
5. Department of Physics, Arizona State University, Tempe, Arizona 85287, USA