Within this dissertation , a number of theories have been discussed such as the 2-D conformal field theory in addition to provided an introduction to (bosonic string) string theory which is underpinned by the vertex operator and DDF operators which were used to create the coherent states. Pre-requisites for creating coherent states such as NambuGoto action, Polyakov action, Virasoro algebra, vertex operator, DelGuidice, DiVecchia and Fubini (DDF) operator have been analysed within the dissertation.
History of nanoparticles in India and synthesis of Mg doped ZnO DMS nanoparticles and it’s characterisation
Mg doped ZnO dilute magnetic semiconductors prepared by chemical method for various doses from 1% to 5%. ZnO and Mg doped ZnO samples were characterized using XRD, SEM and SQUID techniques to study the structural, morphological and magnetic properties respectively. The XRD data of ZnO sample showed the peaks at 31.420, 34.160, 360, 47.460, 56.380, 62.660, 67.760, and 76.940 corresponding to the lattice planes (100), (002), (101), (102), (110), (103), (112), and (202) respectively. The intensity of these peaks was found to be reducing with doping percentage. FWHM of samples varies with the doping percentage. SQUID technique showed ferromagnetic behaviors of all doped samples. The Curie temperature for doped samples showed ferromagnetism above room temperature. SEM technique showed the nano rods in the samples and size of nanorods were found to be in the range of 20-50 nm. As the doping is increased, agglomeration in ZnO takes place which changes its shape of nanorods.
