[1] GVM Girls Coll, Electroceram Res Lab, Sonepat 131001, India
[2] Hindu Coll, Dept Phys, Sonepat 131001, India
[3] GVM Girls Coll, Dept Phys, Sonepat 131001, India
[4] Thapar Univ, Sch Phys & Mat Sci, Patiala 147004, Punjab, India
[5] Solid State Phys Lab, Delhi 110054, India