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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The results of scientific workshop: Spin-polarized current and spin-transfer torque

According to the results of the scientific workshop I want to publish final presentation and put it to the free access, you can find it by the link: Download

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Fun with very large numbers from R. Baillie

I have found a link to an interesting paper in a one social network. Robert Baille shows a few tricks with «almost» true functions: they can be true in the huge interval of their arguments, but fail for the other their values. And numerical methods will fail for direct check. Link…

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Scientific workshop: Spin-polarized current and spin-transfer torque

I am pleased to invite everyone to the scientific workshop, which will be held on 14th January at the Bogolyubov Institute for Theoretical Physics (14-b, Metrolohichna str.Kiev, Ukraine) and will start at 3 PM. On this workshop I want to tell about the nature of spin-polarized current in magnetic multilayers…

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