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In the present study Zinc Oxide (ZnO) nanoparticles and Rare Earth (RE) ion Cerium (Ce) doped ZnO nanoparticles were synthesized by chemical precipitation technique. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscope (TEM), photoluminescence spectroscopy (PL), UV-visible spectroscopy and ferromagnetism behavior at room temperature. The XRD and EDX analysis revealed that Ce doped ZnO pattern matched with the ZnO pattern i.e. they exhibited hexagonal wurtzite structure and Ce ions were successfully incorporated into the ZnO nanoparticles. TEM images illustrated the average diameter of synthesized nanoparticles. The average diameter of ZnO and Ce doped ZnO nanoparticles was around 20 nm. PL measurements revealed that ZnO nanoparticles and Ce doped ZnO nanoparticles had an UV emission and a green emission while the Ce ions doping induced a red shift in the UV emission with broadening in the green emission. Direct type of transition of band gaps was confirmed by transmission spectra occurring at 3.5 and 3.2 eV respectively for ZnO nanoparticles and Ce doped ZnO nanoparticles i.e. decrease of band gap energy with doping of Ce ions in ZnO nanoparticles. The magnetization study on the Ce doped ZnO nanoparticles exposed outstanding ferromagnetism property at room temperature.

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In this paper we study the influence of Dzyaloshinskii-Moriya (DM) interaction on quantum correlations in two qubit Werner states and maximally entangled mixed states (MEMS). We consider our system as a closed system of a qubits pair and one auxiliary qubit which interact with any one of the qubit of the pair through DM interaction. We show that DM interaction, taken along any direction (x or y or z), does not affect two qubit Werner states. On the other hand the MEMS are affected by x and z components of DM interaction and remain unaffected by the y component. Further, we find that the state (i.e probability amplitude) of auxiliary qubit do not affect the quantum correlations in both the states, only DM interaction strength influences the quantum correlations. So one can avoid the intention to prepare the specific state of auxiliary qubit to manipulate the quantum correlations in both the states. We mention here that avoiding the preparation of state can contribute to cost reduction in quantum information processing. We also observe the phenomenon of entanglement sudden death in the present study.