Valley Susceptibility of an Interacting Two-Dimensional Electron System
Valley Susceptibility of an Interacting Two-Dimensional Electron System
We report direct measurements of the valley susceptibility, the change of valley population in response to an applied symmetry-breaking strain, in an AlAs two-dimensional electron system. As the two-dimensional density is reduced, the valley susceptibility dramatically increases relative to its band value, reflecting the system's strong electron-electron interaction. The increase …