Related papers: Spin-droplets in confined quantum Hall systems
We study the formation and characteristics of "spin droplets",i.e., compact spin-polarized configurations in the highest occupied Landau level, in an etched quantum Hall device at filling factors $2\leq\nu\leq3$. The confining potential for…
A theory of electronic properties of a spin-singlet quantum Hall droplet at filling factor $\nu=2$ in a parabolic quantum dot is developed. The excitation spectrum and the stability of the droplet due to the transfer of electrons into the…
When a gas of electrons is confined to two dimensions, application of a strong magnetic field may lead to startling phenomena such as emergence of electron pairing. According to a theory this manifests itself as appearance of the fractional…
In this work, a quantum dot that is defined asymmetrically by electrostatic means induced on a GaAs/AlGaAs heterostructure is investigated to unravel the effect of geometric constrains on the formation of spin droplets under quantised Hall…
The possibility of a novel type of semiconductor quantum dots obtained by spatially modulating the spin-orbit coupling intensity in III-V heterostructures is discussed. Using the effective mass model we predict confined one-electron states…
We have measured electron transport through a vertical quantum dot containing a tunable number of electrons between 0 and 40. Over some region in magnetic field the electrons are spin polarized and occupy successive angular momentum states,…
Quantum Hall states at filling fraction $\nu$=5/2 are examined by numerical diagonalization. Spin-polarized and -unpolarized states of systems with $N\le 18$ electrons are studied, neglecting effects of Landau level mixing. We find that the…
We study a quantum point contact in the fractional quantum Hall regime at Landau level filling factors 1/3 and 5/2. By using exact diagonalizations in the cylinder geometry we identify the edge modes in the presence of a parabolic confining…
We studied neutral excitations in a two-dimensional electron system with an orbital momentum $\Delta M = 1$ and spin projection over magnetic field axis $\Delta S_z = 1$ in the vicinity of a filling factor of 3/2. It is shown that the 3/2…
We study a two-dimensional cylindrically-symmetric electron droplet separated from a surrounding electron ring by a tunable barrier using the exact diagonalization method. The magnetic field is assumed strong so that the electrons become…
The double fractional quantum Hall system of spin 1/2 electrons is numerically studied to predict that there exists a novel spin-unpolarized quantum liquid specific to the multi-species system, which exemplifies a link between the spin…
Double layer two-dimensional electron systems at high perpendicular magnetic field are used to realize magnetic tunnel junctions in which the electrons at the Fermi level in the two layers have either parallel or anti-parallel spin…
We present a theory and Coulomb and Spin Blockade spectroscopy experiments on quantum Hall droplets with controlled electron numbers (N1,N2) in laterally coupled gated quantum dots. The theory is based on the configuration interaction…
We present experimental and theoretical results on a new regime in quantum dots in which the filling factor 2 singlet state is replaced by new spin polarized phases. We make use of spin blockade spectroscopy to identify the transition to…
We explore the characteristics of equilibrium tunneling of electrons from a 3D electrode into a high mobility 2D electron system. For most 2D Landau level filling factors, we find that tunneling can be characterized by a single,…
In this article we discuss the ground state of a parabolically confined quantum dots in the limit of very strong magnetic fields where the electron system is completely spin-polarized and all electrons are in the lowest Landau level.…
Using spin-density-functional theory, we study the electronic states of a two-dimensional parabolic quantum dot with up to N=58 electrons. We observe a shell structure for the filling of the dot with electrons. Hund's rule determines the…
We study the spin relaxation in an interacting two--dimensional electron gas in a strong magnetic field for the case that the electron density is close to filling just one Landau sub--level of one spin projection, i.e., for filling factor…
We have discovered a new example of quantum spin liquid which is a superconducting (SC) phase in 2D electron system close to electronic topological transition. As a quantum spin liquid in low dimensional localized spin systems it is…
We review recent theoretical and experimental developments concerning collective spin excitations in two-dimensional electron liquid (2DEL) systems, with particular emphasis on the interplay between many-body and spin-orbit effects, as well…