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The mechanism of spontaneous exchange bias (SEB) and the dominant factor of its blocking temperature are still unclear in Heusler alloys. Here, the related investigations are performed in Mn2Ni1.5Al0.5 Heusler alloys with SEB. The results of both magnetic measurements and first-principles calculations confirmed that spin frustrated and unfrustrated antiferromagnetic (AFM) states coexist there and they have different magnetic anisotropies, which are essential for SEB. Based on a series of measurement strategies, we demonstrate that the frustrated AFM state undergoes a first-order magnetic transition to the superferromagnet (SFM) state with the help of an external magnetic field, and SFM is retained due to the first-order property of the magnetic transition. SEB originates from the interface coupling of multiple sublattices between the unfrustrated AFM state and SFM state. By analyzing the Arrott plot using the Landau model, we found that the internal field of the system dominates the blocking temperature of SEB, which paves the way for improving the blocking temperature.
We report the observation of large exchange bias in Ni50-xCoxMn38Sb12 Heusler alloys with x=0, 2, 3, 4, 5, which is attributed to the coexistence of ferromagnetic and antiferromagnetic phases in the martensitic phase. The phase coexistence is possibl
In this work we report the synthesis and structural, electronic and magnetic properties of La1.5Ca0.5CoMnO6 double-perovskite. This is a re-entrant spin cluster material which exhibits a non-negligible negative exchange bias effect when it is cooled
Density-functional studies of the electronic structures and exchange interaction parameters have been performed for a series of ferromagnetic full Heusler alloys of general formula Co$_2$MnZ (Z = Ga, Si, Ge, Sn), Rh$_2$MnZ (Z = Ge, Sn, Pb), Ni$_2$MnS
The discovery of materials with improved functionality can be accelerated by rational material design. Heusler compounds with tunable magnetic sublattices allow to implement this concept to achieve novel magnetic properties. Here, we have designed a
A Co$_2$FeSi (CFS) film with L2$_1$ structure was irradiated with different fluences of 30 keV Ga$^+$ ions. Structural modifications were subsequently studied using the longitudinal (LMOKE) and quadratic (QMOKE) magneto-optical Kerr effect. Both the