Spontaneous Zero-Field Cooling Exchange Bias in Ni–Co–Mn–Sn Metamagnetic Heusler Sputtered Film

Abstract

Metamagnetic off-stoichiometric Heusler alloys are actively being investigated because of their great potential as magnetocaloric materials. These properties are intimately related to the nanoscale homogeneity of their magnetic properties, mainly due to a strong influence of the nature of the exchange interactions between Mn atoms on the magnetism of the alloys. In this work, a spontaneous exchange bias phenomenon on a Ni–Co–Mn–Sn metamagnetic Heusler sputtered film is presented and studied in detail. More particularly, a series of DC magnetization curves measured as a function of the temperature demonstrates that the system exhibits canonical spin glass-like features. After a careful study of the field-cooling and zero-field-cooling curves measured on this system, the existence of magnetic inhomogeneities is inferred, as a consequence of the competition between ferromagnetic and antiferromagnetic exchange interactions between Mn atoms. Further AC susceptibility measurements on this system demonstrate that the underlying exchange bias phenomenon can be attributed to a magnetic clusters model based on superferromagnetic-like interactions present in the film. These findings suggest that the spontaneous exchange bias exhibited by the studied system is a consequence of the formation of this superferromagnetic-like state.

Competition of Magnetic Anisotropies in Permalloy Antidot Lattices

“…Many current technological developments related to recording media are tied to the study and generation of novel magnetic materials in the form of thin films. These include floating solid-state thin films for dynamically reconfigurable functional nanodevices [1], thin films undergoing all-optical switching phenomena for magnetic recording media [2], thin films undergoing magnetic phase transitions [3], and the exploitation of static and dynamic magnetic properties of Heusler alloy thin films towards their implementation in recording media [4,5]. Patterned magnetic thin films are a particular subgroup of interesting magnetic materials being developed for current and future technological applications, including the study of magnetic memories through patterned topological insulator materials [6], magnetic skyrmions [7], and artificially frustrated nanostructured systems [8,9].…”

Synthesis, Development and Characterization of Magnetic Nanomaterials

“…In this Special Issue, there are research articles that focus on the thin film growth of ferromagnetic/semiconducting heterostructures and their relation to structural, magnetic, and transport properties [ 1 , 2 , 3 , 4 ], as well as Heusler alloys with ferromagnetic and Weyl semimetals behavior [ 1 , 5 ].…”