A theoretical study on orbital magnetism of mesoscopic ring systems

Spatial distribution of current and resultant magnetization of mesoscopic ring systems with finite width are investigated in various regimes of temperature and magnetic field based on the exactly solvable model. The Aharonov–Bohm (AB) oscillation is observed in low temperatures when electrons occupy only one Landau sublevel. When several Landau sublevels are occupied, the coherence of the AB oscillation is destroyed and mesoscopic fluctuations appear instead. The finite Landau sublevels leads to also de Haas-van Alphen oscillations in relatively low temperatures. In high temperatures, the Landau diamagnetism is observed like in the disk systems.