Perpendicular magnetic anisotropy of Pd/Co₂MnSi/MgAl₂O₄/Pd structure films

Abstract

The existence of strong perpendicular magnetic anisotropy (PMA) with a K eff value of 0.579 × 10 6 erg cm −3 was observed in Pd(6 nm)/Co 2 MnSi(5 nm)/MgAl 2 O 4 (1 nm) trilayers which were prepared at a substrate temperature of 350 °C. It was found that introducing proper oxygen (Ar:O 2 = 18:2) in the oxide preparation process is crucial for the acquisition of PMA. In addition, PMA is also found to be strongly sensitive to the thickness of the Co 2 MnSi (CMS) and MgAl 2 O 4 (MAO) layers. The PMA can be regulated in a wider range of t CMS (4-5.7 nm), and the maximum t CMS of PMA can be maintained at 5.7 nm. For t CMS = 5 nm, the structure can maintain PMA under the condition of t MAO of 0.9-1.3 nm.

Perpendicular magnetic anisotropy of Pd/Co2 MnSi/NiFe2O4/Pd multilayers on F-mica substrates

“…This is because the oxygen loss and the oxygen vacancy in the NFO lead to insufficient Co-O orbital hybridization at the CMS/NFO interface, which resulting in a weak interface effect of CMS/NFO. [17,31] The close to 1 of squareness and large R Hall can be observed at the T O 2 ≥ 5 min, showing that the sample exhibited strong PMA. The R Hall and H C of the sample remain basically unchanged as T O 2 continues to increase.…”

Effects of Pd- and Ta-buffer layer on magnetic and interfacial perpendicular properties of sputtered Co2FeSi/MgO heterostructures

“…The magnetocrystalline anisotropy of the alloy is weak due to the symmetric cubic structure, hence, PMA cannot be exhibited in the individual alloy films. It has been revealed that PMA can be built in lots of Co-based Heusler alloys such as Co 2 (Fe,Mn)Al and Co 2 Fe(Mn.Al)Si, sandwiched by MgO and heavy metals [22][23][24][25][26][27][28][29][30]. The PMA in the structures is supposed to originate from the orbital hybridization or alloying effects at the interfaces [31,32].…”

Efficient magnetization switching induced by spin–orbit torque in perpendicularly magnetized Mn1+xCo2−xAl Heusler alloys

“…8,9 However, achieving PMA in Co-based Heusler alloys is still challenging due to their typical cubic crystal structures. 10 Nevertheless, interfacial PMA has been achieved in Co 2 FeSi (CFS), 11 Co 2 FeAl 0.5 Si 0.5 (CFAS), 11 Co 2 FeAl (CFA), 12,13 and Co 2 MnSi (CMS) 14,15 Heusler alloys when they are in contact with oxides, heavy metals (HMs), or perpendicular magnetized film/seed layers, respectively. Although a large TMR ratio of 91% has been experimentally demonstrated at room temperature in p-MTJ with a CFA electrode, 16 it is still much lower than that of 217% in CMS/MgO/CMS MTJ with in-plane magnetic anisotropy.…”