相关论文: Symmetry-determined generalized ferromagnetism in …
The properties of a two-dimensional electron gas (2DEG) in a semiconductor host with two valleys related by an underlying $C_4$ rotational symmetry are studied using Hartree-Fock (HF) and various other many-body approaches. A familiar…
Valleytronics is rapidly emerging as an exciting area of basic and applied research. In two dimensional systems, valley polarisation can dramatically modify physical properties through electron-electron interactions as demonstrated by such…
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…
In a graphene Landau level (LL), strong Coulomb interactions and the fourfold spin/valley degeneracy lead to an approximate SU(4) isospin symmetry. At partial filling, exchange interactions can spontaneously break this symmetry, manifesting…
An argument is made on the existence of a low-temperature itinerant antiferromagnetic (AF) spin alignment, rather than persistent helical (PH), in the ground state of a two dimensional electron gas in a semiconductor quantum well with…
Valley polarization and altermagnetism are two emerging fundamental phenomena in condensed matter physics, offering unprecedented opportunites for information encoding and processing in novel energy-efficient devices. By coupling valley and…
Electrons are offered a valley degree of freedom in presence of particular lattice structures. Manipulating valley degeneracy is the subject matter of an emerging field of investigation, mostly focused on charge transport in graphene. In…
We study the spin-polarization mechanism in the highly dense nuclear matter with the relativistic mean-field approach. In the relativistic Hartree-Fock framework we find that there are two kinds of spin-spin interaction channels, which are…
Ferro-valleytricity, a fundamental phenomenon that manifests spontaneous valley polarization, is generally considered to occur in two-dimensional (2D) materials with out-of-plane magnetization. Here, we propose a mechanism to realize…
The generation and control of spin- and valley-polarization in antiferromagnets (AFMs) have garnered increasing attention due to their potential for enabling faster and more stable multifunctional spintronic and valleytronic memory and…
The electron's charge and spin degrees of freedom are at the core of modern electronic devices. With the in-depth investigation of two-dimensional materials, another degree of freedom, valley, has also attracted tremendous research…
We present a first principles investigation of the electronic properties of monolayer WS$_2$ coated with an overlayer of Fe. Our ab initio calculations reveal that the system is a half-metallic ferromagnet with a gap of $\sim 1$ eV for the…
Enhancement of the electron spin polarization in a correlated two-layer two-dimensional electron system at a total Landau level filling factor of one is reported. Using resistively detected nuclear magnetic resonance, we demonstrate that…
Novel broken symmetry states can spontaneously form due to Coulomb interactions in electronic systems with multiple internal degrees of freedom. Multi-valley materials offer an especially rich setting for the emergence of such states, which…
Valley, the energy extrema in the electronic band structure at momentum space, is regarded as a new degree of freedom of electrons, in addition to charge and spin. The studies focused on valley degree of freedom now form an emerging field…
When Landau levels (LLs) become degenerate near the Fermi energy in the quantum Hall regime, interaction effects can drastically modify the electronic ground state. We study the quantum Hall ferromagnet formed in a two-dimensional hole gas…
The interplay between quantum Hall ordering and spontaneously broken "internal" symmetries in two-dimensional electron systems with spin or pseudospin degrees of freedom gives rise to a variety of interesting phenomena, including novel…
Spin waves in ferromagnetic materials are predominantly characterized by right-handed circular polarization due to symmetry breaking induced by net magnetization. However, magnetic interactions, including the external magnetic field,…
We uncover a new pathway towards multiferroicity, showing how magnetism can drive ferroelectricity without relying on inversion symmetry breaking of the magnetic ordering. Our free-energy analysis demonstrates that any commensurate…
We investigate superconducting pairing tendencies of a two-dimensional electron fluid with both valley and spin degrees of freedom, both without and in the presence of an in-plane magnetic field. We present suggestive theoretical arguments…