Curvature Effects in Thin Magnetic Shells

The submbicron-scaled magnetism of solid state is a rapidly developing research area with a promising applied potential. Nanomagnets are often considered as elements of fast nonvolatile memory devices of high density. Up to now the theoretical study in this direction was restricted mostly by planar structures. In the current research…

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OOMMF Utilities 1.0

Object Oriented Micromagnetic Framework (OOMMF) is free, portable, extensible public domain micromagnetic program and associated tools, which was developed at the National Institute of Standards and Technology (NIST). OOMMF is very powerful and useful tool which can be thinly configured for different micromagnetic studies, but at the same time, it…

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Periodic magnetic structures generated by spin-polarized currents in nanostripes

We investigated the influence of a spin-polarized current on long ferromagnetic nanostripes. The magnetization behavior is analyzed for all range of the applied currents, up to the saturation. It is shown that the saturation current is a nonmonotonic function of the stripe width. For a stripe width increasing it approaches…

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Regular and chaotic vortex core reversal by a resonant perpendicular magnetic field

We predict the regular and chaotic dynamics of the vortex polarity under the action of perpendicular ac magnetic field and propose a simple analytical description in terms of a reduced vortex core model. Phys. Rev. B, 88, 014432 (2013), 10.1103/PhysRevB.88.014432, PDF.

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How to save intermediate result of calculations in Mathematica

Sometimes, one needs to make long-time pleriminary calculations in Mathematica to obtain expressions for further work. It is not convenien to make them every time when notebook opens again. An easy (but may be machine-dependent) way is to use DumpSave function. How it works. For example, we have a few…

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Семінар «Спіновий струм і солітони в антиферомагнетиках»

У понеділок, 29 травня, в 11:00 відбудеться семінар на тему «Спіновий струм і солітони в антиферомагнетиках», доповідач Олександр Васильович Пилиповський. Місце проведення: Інститут теоретичної фізики імені Боголюбова. Значна кількість штучних і природних антиферомагнетиків, а також високі значення власних частот, які сягають ТГц, привертають значну увагу до їх експериментального і теоретичного дослідження. На…

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Семинар «Магнитоэлектрические эффекты в композитных мультиферроиках»

15 апреля (понедельник) в Институте теоретической физики им. Боголюбова состоится семинар «Магнитоэлектрические эффекты в композитных мультиферроиках». Докладчик: Максим Александрович Попов, к.ф.-м.н., сотрудник Киевского национального университета имени Тараса Шевченка. Начало в 11:00, аудитория №322. Аннотация: Зависляк И.В., д.ф.-м.н., проф., Сохацкий В.П., к.ф.-м.н., доц., Попов М.А., к.ф.-м.н., м.н.с. Дан обзор магнитоэлектрических явлений…

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Nmag console commands in a nutshell

Nmag is a python-based micromagnetic simulator for finite elements mesh. First we add the path and one alias for a comfort work to our bashrc from <nsim>/bin directory: echo "export PATH=\$PATH:`pwd`" >> ~/.bashrc echo "alias nmeshimportg='`pwd`/nmesimport –gmsh'" >> ~/.bashrc Convert the mesh in Version ASCII v2.x format to Version 1:…

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Some tips for MPI and cluster usage

Note, that all information below may not be suitable for every computing cluster due to many differences in operation systems and local settings for user management and parallelization software. Available modules. Command $ module avail gives the list of available modules, such as mpi/openmpi/1.3.2/intel for example. Command «module load <modulename>», where <modulename>…

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Multithreading OOMMF in Linux

Today I want to say some few words about the multithreading OOMMF in Linux. As I know in Windows the last versions of OOMMF, like 12a4 and later (OOMMF), are basically could keep more than 1 thread and accelerate the simulations by paralleling calculations, but you may use for this multithreading Tcl/Tk.  In the…

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