Related papers: Spin-independent effective mass in a valley-degene…
The effective mass at the Fermi level is measured in the strongly interacting two-dimensional (2D) electron system in ultra-clean SiGe/Si/SiGe quantum wells in the low-temperature limit in tilted magnetic fields. At low electron densities,…
Collective charge-density modes (plasmons) of the clean two-dimensional unpolarized electron gas are stable, for momentum conservation prevents them from decaying into single-particle excitations. Collective spin-density modes (spin…
We have measured the effective mass, m, and Lande g-factor in very dilute two-dimensional electron systems in silicon. Two independent methods have been used: (i) measurements of the magnetic field required to fully polarize the electrons'…
A remarkably long-lived spin plasmon may exist in two-dimensional electron liquids with imbalanced spin up and spin down population. Predictions for this interesting mode by Agarwal et al. [Phys. Rev. B 90, 155409 (2014)] are based on the…
Semiclassical expansion of the Wigner function for spin-1/2 fermions having an effective spacetime-dependent mass is used to analyze spin-polarization effects. The existing framework is reformulated to obtain a differential equation…
We have accurately measured the effective mass in a dilute two-dimensional electron system in silicon by analyzing temperature dependence of the Shubnikov-de Haas oscillations in the low-temperature limit. A sharp increase of the effective…
We measure the effective mass (m*) of interacting two-dimensional electrons confined to an AlAs quantum well while we change the conduction-band valley occupation and the spin polarization via the application of strain and magnetic field,…
We investigate the low-lying compression modes of a unitary Fermi gas with imbalanced spin populations. For low polarization, the strong coupling between the two spin components leads to a hydrodynamic behavior of the cloud. For large…
We observe a dramatic reduction in the degree of spin-polarization of a two-dimensional electron gas in a magnetic field when the Fermi energy moves off the mid-point of the spin-gap of the lowest Landau level, $\nu=1$. This rapid decay of…
Using the Schr\"odinger-Poisson system in this paper the basic quantum features of plasmon excitations in a free noninteracting electron gas with arbitrary degeneracy is investigated. The standing wave solution of the free electron gas is…
Measurements of spin dynamics of electrons in a degenerate two dimensional electron gas, where the Dyakonov-Perel mechanism is dominant, have been used to investigate the electron scattering time (tp*) as a function of energy near the Fermi…
We explore a generalization of nonrelativistic fermionic statistics that interpolates between bosons and fermions, in which up to $K$ particles may occupy a single-particle state. We show that it can be mapped exactly to $K$ flavors of…
We study the collective charge excitations (plasmons) in spin polarized graphene, and derive explicit expressions for their dispersion in the undamped regime. From this, we are able to calculate the critical wave vector beyond which the…
In two-dimensional electron systems confined to wide AlAs quantum wells, composite fermions around the filling factor $\nu$ = 3/2 are fully spin polarized but possess a valley degree of freedom. Here we measure the energy needed to…
We develop the theory of collective modes supported by a Fermi liquid of electrons in pristine graphene. Under reasonable assumptions regarding the electron-electron interaction, all the modes but the plasmon are over-damped. In addition to…
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…
We study by Monte Carlo methods the thermodynamics of a spin polarized gas of non-relativistic fermions in 1+1 dimensions. The main result of this work is that our action suffers no significant sign problem for any spin polarization in the…
Spin density matrices of the system, containing arbitrary even number N of indistinguishable fermions with spin S = 1/2, described by antisymmetric wave function, have been calculated. The indistinguishability and the Pauli principles are…
We study collective excitations in a helical electron liquid on a surface of three-dimensional topological insulator. Electron in helical liquid obeys Dirac-like equation for massless particless and direction of its spin is strictly…
We find that the spin susceptibility of a two-dimensional electron system with valley degeneracy does not grow critically at low densities, at variance with experimental results [A. Shashkin et al., Phys. Rev. Lett. 96, 036403 (2006)]. We…