相关论文: (Ir-)Reversibility and thermal equilibrium in magn…
The influence of long-range dipole interactions on two dimensional magnetism has been studied extensively in the spin-reorientation transition of ferromagnetic ultrathin films. Although there is a great deal of experimental information on…
We demonstrate that the reorientation transition from out-of-plane to in-plane magnetization with decreasing temperature as observed experimentally in Ni-films on Cu(001) can be explained on a microscopic basis. Using a combination of mean…
The ability to make controlled patterns of magnetic structures within a nonmagnetic background is essential for several types of existing and proposed technologies. Such patterns provide the foundation of magnetic memory and logic devices,…
Domain phases in ultrathin Fe/Ni/W(110) films with perpendicular anisotropy have been studied using the ac magnetic susceptibility. Dynamics on time scales of minutes to hours were probed by quenching the system from high temperature to the…
The properties of ultrathin films have been studied within the framework of Ising model and the method of random-field interactions. It is shown that the Curie temperature is inversely proportional to the number of layers. Critical exponent…
We analyze the finite temperature phase diagram of ultrathin magnetic films by introducing a mean field theory, valid in the low anisotropy regime, i.e., close to de Spin Reorientation Transition. The theoretical results are compared with…
We introduce a new coarse grain model capable of describing the phase behavior of two dimensional ferromagnetic systems with competing exchange and dipolar interactions, as well as an external magnetic field. An improved expression for the…
We show that the mean field phase diagram of the dipolar frustrated ferromagnet in an external field presents an inverse transition in the field-temperature plane. The presence of this type of transition has recently been observed…
A long standing problem of domain switching process - how domains nucleate - is examined in ultrathin ferroelectric films. We demonstrate that the large depolarization fields in ultrathin films could significantly lower the nucleation…
Ferromagnetism and electrical insulation are often at odds, signifying an inherent trade off. The simultaneous optimization of both in one material, essential for advancing spintronics and topological electronics, necessitates the…
Measurements of resistance vs. temperature have been carried out on a sequence of quench-condensed ultrathin films of amorphous bismuth (a-Bi). The resistance below about 0.1K was found to be temperature independent in a range of films with…
We employ metadynamics simulations to calculate the free energy landscape of thin ferromagnetic films and perform a systematic study of the temperature dependence of magnetic anisotropy and of the spin-reorientation transitions. By using a…
Patterns of ferroic domains and domain walls are being intensively studied to implement new logic schemes. Any technological application of such objects depends on a detailed understanding of them. This study analyzes patterns of…
The nonequilibrium magnetic domain structure of growing ultrathin ferromagnetic films with a realistic atomic structure is studied as a function of coverage and temperature. We apply a kinetic Monte Carlo method to a micromagnetic model…
Pinning magnetization in a ferromagnetic thin film is commonly realized through exchange biasing with an adjacent antiferromagnet. Field-cooling from above the N\'{e}el temperature is a reliable yet slow re-pinning method in exchange-biased…
Nanoscale ferroelectric topologies such as vortices, anti-vortices, bubble patterns etc. are stabilized in thin films by a delicate balance of both mechanical and electrical boundary conditions. A systematic understanding of the phase…
The reorientation transition of the magnetization of ferromagnetic films is studied on a microscopic basis within a Heisenberg spin model. Using a modified mean field formulation it is possible to calculate properties of magnetic thin films…
We studied the phase diagram of thin ferroelectric films with incommensurate phases and semiconductor properties within the framework of Landau-Ginzburg-Devonshire theory. We performed both analytical calculations and phase-field modelling…
The equilibrium phase diagram of a two-dimensional Ising model with competing exchange and dipolar interactions is analyzed using a Monte Carlo simulation technique. We consider the low temperature region of the (delta,T) phase diagram…
Thermodynamic theory is developed for the ferroelectric phase transition of an ultrathin film in equilibrium with a chemical environment that supplies ionic species to compensate its surface. Equations of state and free energy expressions…