[1] Nanyang Technol Univ, Sch Phys & Math Sci, Div Phys & Appl Phys, Singapore 637371, Singapore
[2] Nanyang Technol Univ, Coll Engn, Mat Sci & Engn, Singapore 637371, Singapore
[3] Robert Bosch SEA Pte Ltd, Corp Res, Res & Technol Ctr Asia Pacific 1, Singapore 573943, Singapore
[4] Agcy Sci Technol & Res, Inst High Performance Comp, Singapore 138632, Singapore