Modulating the Magnetic Coupling in Paramagnetic Co Nanoparticles Embedded in Tris(8-hydroxyquinoline)aluminum for Spintronics Applications

Abstract

Tailoring the organic–inorganic heterostructure through nanotechnology and molecular engineering is a promising route to achieve high performances of spintronics. Tris­(8-hydroxy­quinoline)­aluminum (Alq3) with effective electron-transport properties and excellent emitting efficiency as an organic light-emitting diode has been employed as a nonmagnetic layer and integrated with magnetic electrodes to become an effective spin filter in organic spintronics. The device performances are strongly influenced by the interfacial spin polarization at the organic–ferromagnetic heterojunction. We therefore manipulated the magnetic exchange coupling of a hybrid organic–ferromagnetic complex through coevaporation to produce hybrid nanoclusters for modulating the degree of hybridization between Co and Alq3. Paramagnetic Alq3–Co nanoclusters with varied volume ratios of Alq3 to Co were fabricated. The results demonstrate that the extent of hybrid N correlates with the ratio of the deposited amount of Co in three paramagnetic nanocluster thin films. The coercivity (H c) and magnetic moment of all paramagnetic thin films correlated strongly with the degree of hybridization of Co clusters in the coevaporated complex. Notably, the magnetic moment is maximized with the optimized hybrid structure that expresses efficient spin filtering for molecular/organic spintronics.

Unraveling Exchange Coupling in Ferrites Nano‐Heterostructures

“…Our nano-heterostructures are the result of the high control of interface epitaxy achieved through controlled annealing, which produces a [100]// [1][2][3][4][5][6][7][8][9][10] texture between SFO and CFO induced by the (111) of preformed CFO (as depicted in Figure 6c, together with a schematic of the reversal). Knowing that the easy axes are not parallel to each other (while the SFO core has an out-of-plane easy axis, the CFO layer tends to lie along the [100] axis) [60,61] induce to believe that the strong coupling is not due to dipolar interaction between the two materials, as it may be the case for such misinterpretation if the easy axes were aligned.…”

“…Magnetic interactions play a crucial role in the effectiveness of magnetic nanomaterials in industrial applications, such as magnetic recording, permanent magnets, and spintronics. [1][2][3][4][5] Functional oxide nanocomposites (NCs) have demonstrated great potential in this regard, based on the combination of DOI: 10.1002/smll.202304152 two or more phases to create functional materials with tunable magnetic properties. [6][7][8][9][10] In this context, multiphase nano-heterostructures have attracted a huge interest in developing a new class of materials with enhanced magnetic properties.…”