Mesoscopic exchange in ferromagnetic globular alloy

Abstract

In a nano- or micro- film consisting of alternating magnetic and non-magnetic layers, magnetic layers spin-polarize the spontaneous currents in the between paramagnetic layer and, thereby, extra-magnetize themselves. However, only a spin-polarized current has been observed in heterogeneous alloys, but not its magnetizing effect. Unfortunately, there is no experimental proof that spin-polarized current magnetizes mesoscopic globules or clusters. Here we show that the MnAs globules spin-polarize electric current in the Cd₃As₂(MnAs)_0.447 globular alloy and additionally magnetizes exchanging by this current. The negative magnetoresistance and the negative non-ohmicity indicate the spin polarization of the current, and the excess magnetization reveals self-magnetizing the globules. We calculated the Cd₃As₂ forbidden gap from the temperature dependence of the Cd₃As₂(MnAs)_0.447 magnetization and, thereby, proved that the spin-polarized current of the Cd₃As₂ intrinsic electrons extra-magnetizes the MnAs globules. The magnetization increase and high non-ohmicity of Cd₃As₂(MnAs)_0.447 at room temperature and low voltages represent globular ferromagnetic alloys as an atractive material to study the spin polarization and non-ohmicity. Such alloys can find applications in nanomagnetoelectronics because they have low coercivity that will be helpful for magnetization manipulation.