Temperature and field hysteresis of the antiferromagnetic-to-ferromagnetic phase transition in epitaxial FeRh films

Large resistivity modulation in mixed-phase metallic systems

“…The strain-mediated resistivity change is large for a metallic/ferroelectric heterostructure system at E-fields of the order of 4B6 kV cm À 1 , rendering the behaviour potentially technologically relevant. This sensitivity is a consequence of the fact that the FM and AFM phases are relatively close in energy near the transition temperature 24 and thus can be interconverted from one to the other by simply straining the lattice parameter of the system. Artificially engineered heterostructures such as spin valves or tunnel junction devices may enhance the control of resistance modulation and therefore make the GER effect found in this work more attractive for applications.…”

“…Although the origin of the phase transition has long been a subject of theoretical studies 20,21 , it is now believed to result from different temperature dependencies of the entropy in the two phases 22,23 . The transition has recently been shown to persist in thin films 17,24 and the substrate dependence of the transition has been exploited in heterostructures of FeRh deposited on ferroelectric BaTiO 3 to induce the FM to AFM transition using an electric field 25 . We report large electric-fieldinduced changes in resistivity in a thin film of the intermetallic FeRh deposited on a piezoelectric substrate and demonstrate that the response results from the competition between coexisting AFM and FM phases with different resistivities.…”

Anomalous metamagnetic-like transition in a FeRh/Fe3Pt interface occurring at T ≈ 120 K in the field-cooled-cooling curves for low magnetic fields

“…The transition temperature is however highly sensitive to small changes out of the equiatomic stoichiometry 4 and microstructural scale. 5,6 The magnetostructural phase transition is of first order kind with a volume expansion of about 1% when entering in the ferromagnetic phase and a temperature hysteresis of the order of 10 K. 1,[7][8][9] These characteristics make thin films of the FeRh system to present a good potential for applications as micro-electromechanical devices. 10 The study which motivated us, performed in the binary thin film of FePt-FeRh presented in Ref.…”

“…3, the jump is estimated to be ≈ 5 × 10 3 emu/cm 3 for a 50 nm thickness while the size of the antiferromagnetic-ferromagnetic (AF-F) transition observed in FeRh in Ref. 7 is of the order of 1.2x10 3 emu/cm 3 , but at a T ≈ 350 K. It should be mentioned that an AF-F transition was observed in a Fe 48 Rh 52 film 10 at T ≈ 100 K, also with a size of the order of 1.2 × 10 3 emu/cm 3 . So the "size" of the metamagnetic-like transition observed here for the FeRh-Fe 3 Pt film appears to be 4 times bigger than the AF-F transition observed for pure FeRh.…”

Design of Co∕Pd multilayer system with antiferromagnetic-to-ferromagnetic phase transition

“…Consequently the energy scales governing the magnetic properties of the two materials are vastly different. At temperatures close to the AF-FM transition in FeRh, the transition can be induced by an external magnetic field, and the transition shifts linearly by about 8 -9 K / T, 12 i.e., for a sample with T AF-FM of approx 100°C a magnetic field of the order of 8 T is required to induce the phase transition at room temperature. In contrast, as shown in Fig.…”