Positive and negative exchange bias effects in the simple perovskite manganite NdMnO3

Abstract

Exchange bias effects were studied in the simple perovskite NdMnO3. Nd3+ ordering is induced by the Mn3+ ferromagnetic component, and they are antiferromagnetically coupled with each other. At 30 K, both negative and positive exchange bias effects are found, which are dependent on the cooling field. The exchange bias fields are around −2400 Oe and 1800 Oe, respectively. Positive and negative exchange bias effects were also observed at 8 K, but the exchange bias fields are only 130 Oe and −120 Oe. The coupling intensity between Nd3+ ordering and Mn3+ ordering, and their initial states determine the polarity of the exchange bias fields.

Influence of Negative Field Cooling on the Exchange Bias Properties of Potassium Split Graphene Nanoribbons

“…consequently couple antiferromagntically to each other, which leads the exchange bias effect. Such positive EB has been observed at 10 T [31]. The noteworthy observation in the present GNRs is that we could see a positive EB with few kOe magnetic fields under the NFC conditions.…”

Room temperature dielectric and magnetic properties of Gd and Ti co-doped BiFeO3 ceramics

“…We are carrying out further investigations in detail on these optimized ceramics. The presence of exchange bias effect in these compounds at room temperature is another fascinating feature which was also reported in similar systems [4,43,46,47] although at low temperature.…”

“…The exchange bias effect usually occurs in ferromagnetic and antiferromagnetic bilayers or multilayers in which the two coercive fields of the magnetic hysteresis loop are not symmetric, and the centre of the magnetic hysteresis loop shifts to the left or right [43,44,46]. Recent investigations also demonstrate that the exchange bias effect can also exist in compounds or composites which allow the coexistence of both a ferromagnetic component and an antiferromagnetic component [43,46,47]. In compounds like NdMnO 3 [46] or La 1−x Pr x CrO 3 [47], the exchange bias effect is different from what appears in bilayer and other interface structures.…”

Magnetic field induced discontinuous spin reorientation in ErFeO3 single crystal

“…DyFeO 3 is the only orthoferrite to show a Morin transition, where the Fe 3þ system spins are reoriented from C 4 to C 1 around 35 K, at which the AFM spins rotate from the a-axis to the b-axis. 15 For all other orthoferrites, such as ErFeO 3 , it is commonly believed that the FM vector F continuously rotates from the c-axis (C 4 ) towards the a-axis (C 2 ) while staying in the ac-plane through the intermediate phase (C 24 ðG xz ; F xz Þ), 16,17 upon cooling below its Neel temperature, as seen in Fig. 1.…”