[1] CMR Inst Technol, Dept Phys, Bengaluru 560037, Karnataka, India
[2] Gopalan Coll Engn, Dept Phys, Bengaluru, Karnataka, India
[3] CMR Inst Technol VTU, Dept Phys, Bengaluru 560037, Karnataka, India
[4] KPR Inst Engn & Technol Autonomous, Dept Phys, Coimbatore 641407, Tamil Nadu, India