Substitution Effect on the Magnetic Interaction of Zn1-x(Co, Al)xO Nanoparticles Studied by μSR

The development of communication and information devices has grown rapidly in recent years. This growth is supported by the reduction of the size of the transistor which can increase the storage capacity, speed, and efficiency of the devices. However, the reduction of the size of the transistor will meet the limit when it continues to be lowered to the atomic size. Heat dissipation and quantum-size effects will cause significant changes in the writing and reading processes which cannot be avoided. One of the solutions to this problem is developing spintronic technologies based on magnetic semiconductors. We have studied the magnetization of semiconductor Zn1-x(Co, Al)xO nanoparticles by using a superconducting quantum interference device magnetometer (SQUID). We found that it shows magnetism even at high temperatures when Al is doped on the ZnO. When Co is doped to the ZnO, it behaves magnetically at 2 K, meanwhile, behaves paramagnetic at 100 K and 300 K. The relationship between magnetic interactions and doping effects is still left to be clarified. Therefore, μSR is needed here to gain a better understanding of the magnetic interactions and confirm the magnetic phase of Zn1-x(Co, Al)xO. In this proposed study, we aim to study the magnetic state of Zn1-x(Co, Al)xO at the base temperature up to room temperature and its magnetic spin fluctuation.