Exchange springs in L1 0 -FePt(110)/A1-FePt bilayer films

Due to its extremely high uniaxial magnetocrystalline anisotropic energy, L1 0 -FePt is being paid attentions in recent years [1, 2]. Practically, ideas should be come up with to reduce the exaggerated switch field of grain without reducing its thermal stability. In hard/soft systems (exchange spring systems), the magnetization reversal is thought to occur by domain nucleation by the soft layer that propagates into the hard layer [3]. Optimizing these structures requires controlling the interlayer exchange and understanding the magnetic reversal pathway. Strong coercivity reduction in FePt(001)/Fe bilayers on MgO(001) substrates had been investigated [4]. Nevertheless, in the applications such as the magnetic layers coated on probes of magnetic force microscopy (MFM), the existence of Fe layer is unfavorable for corrosion resistance, and the fabrication of bilayer structures combining materials with different magnetic characteristics (i. e., different magnetic ordering and magnetic anisotropies) is also needed to allow. In this investigation, L1 0 -FePt(110)/A1-FePt bilayer films with different ordering in FePt(110) layer were deposited on MgO(110) substrates. The magnetic properties related to exchange spring were researched for the potential application in MFM tips.