Effective mass suppression upon complete spin-polarization in an isotropic two-dimensional electron system

Abstract

We measure the effective mass (m*) of interacting two-dimensional electrons confined to a 4.5 nm-wide AlAs quantum well. The electrons in this well occupy a single out-of-plane conduction band valley with an isotropic in-plane Fermi contour. When the electrons are partially spin polarized, m* is larger than its band value and increases as the density is reduced. However, as the system is driven to full spin-polarization via the application of a strong parallel magnetic field, m* is suppressed down to values near or even below the band mass. Our results are consistent with the previously reported measurements on wide AlAs quantum wells where the electrons occupy an in-plane valley with an anisotropic Fermi contour and effective mass, and suggest that the effective mass suppression upon complete spin polarization is a genuine property of interacting two-dimensional electrons.

6 pages, 7 figures, accepted for publication in Phys. Rev. B

References in corpus (9)

• Measurements of the density-dependent many-body electron mass in 2D GaAs/AlGaAs Heterostructures
• Spin-independent origin of the strongly enhanced effective mass in a dilute 2D electron system
• Density dependent spin susceptibility and effective mass in interacting quasi-two dimensional electron systems
• Effective mass suppression in dilute, spin-polarized two-dimensional electron systems
• Spin Polarization Dependence of Carrier Effective Mass in Semiconductor Structures: Spintronic Effective Mass
• Spin Susceptibility of Interacting Two-dimensional Electrons with Anisotropic Effective Mass
• Dependence of Effective Mass on Spin and Valley Degrees of Freedom
• Parallel Magnetic Field Tuning of Valley Splitting in AlAs Two-Dimensional Electrons
• High-mobility AlAs quantum wells with out-of-plane valley occupation

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• Diffusion quantum Monte Carlo calculation of the quasiparticle effective mass of the two-dimensional homogeneous electron gas
• Direct observation of $\Gamma -X$ energy spectrum transition in narrow AlAs quantum wells
• Effective Mass and Spin Susceptibility of Dilute Two-Dimensional Holes in GaAs
• $m^{\ast }$ of two-dimensional electron gas: a neural canonical transformation study
• Tuning Fermi Liquids with polaritonic Cavities
• Spin polarization dependence of quasiparticle properties in graphene
• Quantum Monte Carlo study of the quasiparticle effective mass of the two-dimensional uniform electron liquid
• The electron effective mass in the strongly correlated 2D-uniform electron fluid from finite-temperature calculations