Abstract
We report measurements of the spin susceptibility, , in an AlAs two-dimensional electron system where, via the application of in-plane stress, we transfer electrons from one ellipsoidal conduction-band valley to another ( is the valley degeneracy, and and are the electron effective mass and factor). At a given density, when the two valleys are equally populated (), the measured is smaller than when only one valley is occupied (). This observation counters the common assumption that a two-valley two-dimensional system is effectively more dilute than a single-valley system because of its smaller Fermi energy.
- Received 15 February 2004
DOI:https://doi.org/10.1103/PhysRevLett.92.246804
©2004 American Physical Society