1103.1313 (Enke Liu et al.)

Stable magnetostructural coupling with tunable magnetoresponsive effects
in hexagonal phase-transition ferromagnets    [PDF]

Enke Liu, Wenhong Wang, Lin Feng, Wei Zhu, Guijiang Li, Jinglan Chen, Hongwei Zhang, Guangheng Wu, Chengbao Jiang, Huibin Xu, Frank de Boer

The magnetostructural coupling between the structural and the magnetic
transition plays a crucial role in magnetoresponsive effects in a
martensitic-transition system. A combination of various magnetoresponsive
effects based on this coupling may facilitate the multifunctional applications
of a host material. Here, we demonstrate a possibility to obtain a stable
magnetostructural coupling in a broad temperature window from 350 to 70 K,
showing tunable magnetoresponsive effects, based on simultaneous manipulation
of the phase stability and the magnetic structure by suitable chemical
substitution of iron in MnNiGe. The resultant MnNiGe:Fe exhibits a
magnetic-field-induced martensitic transition from paramagnetic austenite to
ferromagnetic martensite, featuring (i) a large volume increase, (ii) a
distinct magnetization change, (iii) small thermal hysteresis and (iv) a giant
negative magnetocaloric effect. The results indicate that stable
magnetostructural coupling is accessible in hexagonal phase-transition systems
to attain the magnetoresponsive effects with broad tunability.

View original: http://arxiv.org/abs/1103.1313