Magnetic Force Microscopy of Nanostructured Co/Pt Multilayer Films with Perpendicular Magnetization

Abstract

Abstract:We present the results of magnetic force microscopy investigations of domain structures in multilayer [Co (0.5 nm)/Pt (1 nm)] 5 thin film structures (denoted hereafter as Co/Pt) modified by additional Co capping layers and by ion irradiation. It is demonstrated that a Co capping layer essentially changes the domain structure and decreases the threshold of magnetization reversal, due to the formation of noncollinear magnetization in Co/Pt. It is shown that local irradiation with a focused He + ion beam enables the formation of regions with decreased easy-axis anisotropy (magnetic bubbles) that have the inverse magnetization direction in the demagnetized state of Co/Pt. The experimental results demonstrate that the magnetic bubbles can be switched using a probe of a magnetic force microscope. The possible application of these effects for the development of magnetic logic and data storage systems is discussed.

Co metal nanoparticles deposition inside or outside multi-walled carbon nanotubes via facile support pretreatment

“…Surface acid-base properties of the pristine and functionalized MWCNTs at the solid-liquid interface were estimated by determining the PZC according to the standard drift test method (equilibrium pH at high loading) [63][64][65][66]. 1 g of each MWCNT samples was placed in 20 ml of aqueous solutions with different initial values of pH (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13). Then the obtained suspension was stirred on a magnetic stirrer for 1 h at 250 rpm.…”

“…The decoration of multi-walled carbon nanotubes (MWCNTs) by cobalt nanoparticles expands the range of their functional properties by providing them with new magnetic, catalytic, electronic and electro-magnetic characteristics. MWCNTs filled with magnetic Co-containing nanoparticles have been proved to be useful for multiple innovations in nanotechnology [1][2][3], Li/air batteries [4][5][6][7][8], magnetic-storage devices [9], magnetic composites for drug delivery [10,11], catalysts for different processes [12][13][14][15][16][17][18], as well as absorption and microwave irradiation shielding material [19][20][21][22][23][24][25][26][27][28][29][30]. It is generally accepted that the magnetic properties of nanoparticles are determined by many factors, such as chemical composition [20,[31][32][33][34][35], crystallinity [36,37], size [37][38][39][40][41] and shape [35,<...>…”

Understanding the Magnetic Microstructure through Experiments and Machine Learning Algorithms

“…Thus, in the absence of an external magnetic field ( E H = 0), the minimization of the total energy terms leads to the formation of magnetic domains . In reality, it is complicated to predict the simultaneously changing competing magnetic interactions that result in various domain morphologies for perpendicularly magnetized systems. − Now, the characteristic features of magnetic domains in multilayer (ML) films can be controlled by different factors such as growth conditions, the thicknesses of the constituent layers, as well as the application of external stimuli, viz., magnetic field, heat treatment, laser, and ion irradiation . Moreover, the tunable exchange coupling in the exchange spring magnets can significantly control the magnetic microstructure. , Thus, modeling of process-induced magnetic modifications has also been proven to be important in designing highly controlled experiments and predicting new materials and methods.…”

Воздействие поля зонда магнитно-силового микроскопа на скирмионное состояние в модифицированной пленке Co/Pt с перпендикулярной анизотропией

“…Однако в последние годы были развиты новые методы наноструктурирования, основанные на облучении образцов с помощью фокусированных ионных пучков [2,3], что позволяет локально модифицировать свойства пленочных структур без изменения их рельефа. Особенно эффективен данный подход в применении к многослойным тонкопленочным структурам Co/Pt с перпендикулярной намагниченностью, в которых с помощью фокусированных ионных пучков удается локально модифицировать параметр перпендикулярной анизотропии [4][5][6][7]. В частности, в работе [8] было показано, что данный метод позволяет создавать плотные решетки искусственных магнитных скирмионов, которые могут быть применены в качестве среды для записи информации с высокой плотностью.…”