相关论文: Asymmetric magnetic dots: A way to control magneti…
Asymmetric dots as a function of their geometry have been investigated using three-dimensional (3D) object oriented micromagnetic framework (OOMMF) code. The effect of shape asymmetry of the disk on coercivity and remanence is studied.…
Reproducible control of the magnetic vortex state in nanomagnets is of critical importance. We report on chirality control by manipulating the size and/or thickness of asymmetric Co dots. Below a critical diameter and/or thickness,…
The emission spectra of individual self-assembled quantum dots containing a single magnetic Mn atom differ strongly from dot to dot. The differences are explained by the influence of the system geometry, specifically the in-plane asymmetry…
Shape asymmetries in nominally circular nanomagnets provide a potential means for vortex chirality control. However, in realistic arrays their effects are challenging to probe since asymmetric magnetization reversal processes are often…
Effects of magnetic asymmetry on strongly coupled spin-vortex pairs with parallel core polarization and antiparallel chirality in synthetic nanomagnets are investigated. This includes vortex-core length asymmetry, biasing field asymmetry,…
We use density-functional methods to study the effects of an external magnetic field on two-dimensional quantum dots with a rectangular hard-wall confining potential. The increasing magnetic field leads to spin polarization and formation of…
An effective Hamiltonian technique is used to investigate the effect of applying curled electric fields on physical properties of stress-free BiFeO3 dots being under open-circuit electrical boundary conditions. It is discovered that such…
Finite-element micromagnetic simulations are employed to study the chiral symmetry breaking of magnetic vortices, caused by the surface roughness of thin-film magnetic structures. An asymmetry between vortices with different core…
A singular configuration of external static magnetic field in the form of a pointlike vortex polarizes the vacuum of quantized massless spinor field in 2+1-dimensional space-time. This results in an analogue of the Bohm-Aharonov effect: the…
X ray resonant magnetic scattering (XRMS) was used to characterize the magnetization of 2D arrays of trilayer submicron magnets. The interpretation of the data required the understanding of the morphology of the magnets which was also…
Soft magnetic dots in the form of thin rings have unique topological properties. They can be in a vortex state with no vortex core. Here, we study the magnon modes of such systems both analytically and numerically. In an external magnetic…
We use Monte Carlo simulation to study the vortex nucleation on magnetic nanodots at low temperature. In our simulations, we have considered a simple microscopic two-dimensional anisotropic Heisenberg model with term to describe the…
The role of discrete orbital symmetry in mesoscopic physics is manifested in a system consisting of three identical quantum dots forming an equilateral triangle. Under a perpendicular magnetic field, this system demonstrates a unique…
The energy of a displaced magnetic vortex in a cylindrical particle made of isotropic ferromagnetic material (magnetic dot) is calculated taking into account the magnetic dipolar and the exchange interactions. Under the simplifying…
The spin structure in a magnetic dot, which is an example of a quantum few-body system, is studied as a function of exchange coupling strength and dot size with in the semiclassical approximation on a discrete lattice. As the exchange…
We investigate the thermal properties of circular semiconductor quantum dots in high magnetic fields using finite temperature Hartree-Fock techniques. We demonstrate that for a given magnetic field strength quantum dots undergo various…
In this work we study the thermodynamic properties of ultrathin ferromagnetic dots using Monte Carlo simulations. We investigate the vortex density as a function of the temperature and the vortex structure in monolayer dots with…
Similar to atoms and nuclei, semiconductor quantum dots exhibit formation of shells. Predictions of magnetic behavior of the dots are often based on the shell occupancies. Thus, closed-shell quantum dots are assumed to be inherently…
The magnetic field dependence of the electronic properties of \textit{real} single vertical quantum dots in circular and rectangular mesas is investigated within a full three-dimensional multiscale self-consistent approach without any {\it…
We employ the density functional Kohn-Sham method in the local spin-density approximation to study the electronic structure and magnetism of quasi one-dimensional periodic arrays of few-electron quantum dots. At small values of the lattice…