Affiliation: | (1) Department of Physics, Kumaun University, S. S. J. Campus, Almora, 263601, (Uttarakhand), India;(2) Institute of Theoretical Physics, Chinese Academy of Sciences, KITP Building Room No. 6304, Hai Dian Qu Zhong Guan Chun Dong Lu 55 Hao, Beijing, 100080, People’s Republic of China;(3) Present address: Department of Physics, Kumaun University, S. S. J. Campus, Almora, 263601, (Uttarakhand), India |