According to one embodiment, a magnetic device includes a layer stack. The layer stack includes a first ferromagnetic layer, a second ferromagnetic layer, a first nonmagnetic layer between the first ferromagnetic layer and the second ferromagnetic layer, and a second nonmagnetic layer. The first ferromagnetic layer is interposed between the second nonmagnetic layer and the first nonmagnetic layer. The first nonmagnetic layer and the second nonmagnetic layer contain a magnesium oxide (MgO). The first ferromagnetic layer contains a higher amount of boron (B) at an interface with the first nonmagnetic layer than at an interface with the second nonmagnetic layer.