Magnetization of the Fractional Quantum Hall States

We observe electron magnetism originating from fractional quantum Hall states in single-layered GaAs heterojunctions. This magnetization is entirely governed by electron-electron interaction effects. The studies were performed at temperatures between 0.3 and 7 K on gated high-mobility two-dimensional electron systems. We observe oscillations in the magnetic moment at various fractional filling factors, both for ν1, which persist up to 3.8 K. Most prominent features are found at filling factors 13, 23, 45, and 85. In addition, an intrinsic strongly asymmetric magnetization around ν=1 is observed.