[1] Tumkur Univ, Univ Coll Sci, Dept Phys, Tumkur 572103, India
[2] Tumkur Univ, Prof CNR Rao Ctr Adv Mat, Tumkur 572103, India
[3] VTU Affiliat, BMS Inst Technol & Management, Dept Phys, Bangalore 560064, Karnataka, India
[4] Lal Bahadur Shastry Govt First Grade Coll, Dept Phys, Bangalore 560032, Karnataka, India
[5] Dayananda Sagar Univ, Shavige Malleshwara Hills, Bangalore 560078, Karnataka, India
[6] Dayananda Sagar Coll Engn, Dept Chem, Shavige Malleshwara Hills, Bangalore 560078, Karnataka, India
[7] East West Inst Technol, Res Ctr, Dept Sci, Bangalore 560091, Karnataka, India
[8] JSS Acad Tech Educ, Dept Phys, Bangalore 560060, Karnataka, India