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 $\nu <1\mathrm{}$ and $\nu >1\mathrm{}$, which persist up to 3.8 K. Most prominent features are found at filling factors $\frac{1}{3}$, $\frac{2}{3}$, $\frac{4}{5}$, and $\frac{8}{5}$. In addition, an intrinsic strongly asymmetric magnetization around $\nu =1\mathrm{}$ is observed.