Dependence of spin susceptibility of a two-dimensional electron system on the valley degree of freedom

Abstract

We report measurements of the spin susceptibility, $\chi \propto g_v{g}^{\ast }{m}^{\ast }$, in an AlAs two-dimensional electron system where, via the application of in-plane stress, we transfer electrons from one conduction-band valley to another ($g_v$ is the valley degeneracy, and $m^{\ast }$ and $g^{\ast }$ are the electron effective mass and g-factor). At a given density, when the two valleys are equally populated ($g_v=2$), the measured $g^{\ast }{m}^{\ast }$ is smaller than when only one valley is occupied ($g_v=1$). 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.

4 pages, 3 figures

References in corpus (3)

• Valley splitting of AlAs two-dimensional electrons in a perpendicular magnetic field
• Spin-independent origin of the strongly enhanced effective mass in a dilute 2D electron system
• Low-temperature, in situ tunable, uniaxial stress measurements in semiconductors using a piezoelectric actuator

Cited by in corpus (16)

• Valley susceptibility of an interacting two-dimensional electron system
• Band mass anisotropy and the intrinsic metric of fractional quantum Hall systems
• Observation of Quantum Hall Valley Skyrmions
• Valley polarization and susceptibility of composite fermions around nu=3/2
• Observation of Spontaneous Ferromagnetism in a Two-Dimensional Electron System
• Density dependent spin susceptibility and effective mass in interacting quasi-two dimensional electron systems
• Anomalous Spin Polarization of GaAs Two-Dimensional Hole Systems
• Valley polarization assisted spin polarization in two dimensions
• Contrast between spin and valley degrees of freedom
• Spin Susceptibility of Interacting Two-dimensional Electrons with Anisotropic Effective Mass
• Parallel Magnetic Field Tuning of Valley Splitting in AlAs Two-Dimensional Electrons
• Dependence of persistent gaps at Landau level crossings on relative spin
• Density-controlled quantum Hall ferromagnetic transition in a two-dimensional hole system
• Enhancement of valley susceptibility upon complete spin-polarization
• Piezoplasmonics: strain-induced tunability of plasmon resonance in AlAs quantum wells
• Zeeman splitting of interacting two-dimensional electrons with two effective masses