1. Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
2. Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, Texas 78249, United States
3. General Atomics, P.O. Box 85608, San Diego, California 92186 United States
4. Department of Mechanical Engineering, Southern Methodist University, Dallas, Texas 75205, United States