1. Department of Mechanical Engineering, Colorado School of Mines, 1500 Illinois St., Golden, Colorado 80401, United States
2. Materials and Biophysics Group, Department of Applied Physics, S. V. National Institute of Technology, Surat 395007, India
3. Hanse-Wissenschaftskolleg (HWK), Lehmkuhlenbusch 4, 27753 Delmenhorst, Germany