[1] Univ Engn & Technol, Dept Phys, Lahore 54890, Pakistan
[2] Univ Sahiwal, Dept Phys, Sahiwal, Pakistan
[3] Univ Educ, Dept Phys, Lahore, Pakistan
[4] COMSATS Univ Islamabad, Dept Phys, Clean Energy Res Lab CERL, Lahore Campus, Lahore 54000, Pakistan
[5] Linkoping Univ, Semicond Mat, Dept Phys Chem & Biol, Linkoping, Sweden
[6] Huazhong Univ Sci & Technol, Dept Thermal Power & Energy Engn, Wuhan, Peoples R China
[7] Govt Coll Univ, Dept Phys, Lahore, Pakistan