Contents I. Introduction
Great attention has been given to magnetic nanoparticles, important for potential technological applications and manufacture of new devices [1]–[5]. The spherical geometry is the favorite format but is limited to just an active surface (external) for modification; similarly, it would be highly desirable to modify the internal and external surfaces as an alternative. The geometry offers advantages as compared to nanorods due to the internal cavity as a new surface for trapping and transport molecular compounds. Magnetic nanotubes are suitable for applications in biotechnology [6], [7]. Magnetic tubular nanostructures are lower in density than nanowires, then the possibility to float in biological solutions, becoming the nanotubular geometry more useful for in vivo applications [8]. Magnetic nanotubes provide an alternative for several technological applications as vehicle for imaging and drug delivery [9], [10]. The properties and characteristics for cylindrical magnetic nanoparticles are due to the several methods of production [8]–[17]. The main studies about those systems correlated the reduced dimensionality for nanotubes and interesting magnetic properties [18]–[23]. The experimental progress, theoretical calculations, and computer simulations about magnetic nanotubes were performed to analyze their properties (magnetostatic interactions, magnetotransport properties, domain walls propagation, and anisotropy) [19], [24]–[29]. Finding regular behavior of magnetic quantities may be important; this is justified by the desire to ensure the stability of quantities for applications. The micromagnetic approach is widely used to describe the static and dynamic response in ferromagnetic materials. The theory is based on the assumptions that the magnetic system is formed by a set of volume elements, all with a constant magnetic moment, . To solve the micromagnetic equations using computational methods, we have the finite element method and the finite difference method [30]. In this paper, we present a study using micromagnetic simulation with Object Oriented MicroMagnetic Framework (OOMMF) about a well specific size choice for an isolated magnetic nickel nanotube, in order to find a flat behavior in magnetic parameters.
