Oropesa William Gabriel Carreras, Correa Víctor F, Sereni Julián G, García Daniel J, Cornaglia Pablo S
Centro Atómico Bariloche and Instituto Balseiro, CNEA, 8400 Bariloche, Argentina.
J Phys Condens Matter. 2018 Jul 25;30(29):295803. doi: 10.1088/1361-648X/aaca66. Epub 2018 Jun 5.
We present a phenomenological analysis of the magnetoelastic properties of CeCoFeSi at temperatures close to the Néel transition temperature T . Using a Landau functional we provide a qualitative description of the thermal expansion, magnetostriction, magnetization and specific heat data. We show that the available experimental results (Correa et al 2016 J. Phys.: Condens. Matter 28 346003) are consistent with the presence of a structural transition at [Formula: see text] and a strong magnetoelastic coupling. The magnetoelastic coupling presents a Janus-faced effect: while the structural transition is shifted to higher temperatures as the magnetic field is increased, the resulting striction at low temperatures decreases. The strong magnetoelastic coupling and the proximity of the structural transition to the onset temperature for magnetic fluctuations, suggest that the transition could be an analogue of the tetragonal to orthorhombic observed in Fe-based pcnictides.
我们对接近奈尔转变温度(T)的温度下(CeCoFeSi)的磁弹性性质进行了唯象分析。利用朗道泛函，我们对热膨胀、磁致伸缩、磁化强度和比热数据进行了定性描述。我们表明，现有的实验结果（科雷亚等人，2016年，《物理学报：凝聚态物质》，28卷，346003）与在([公式：见正文])处存在结构转变以及强磁弹性耦合相一致。磁弹性耦合呈现出两面性效应：随着磁场增加，结构转变向更高温度移动，而低温下产生的应变减小。强磁弹性耦合以及结构转变与磁涨落起始温度的接近性表明，该转变可能类似于在铁基磷族化合物中观察到的四方相向正交相的转变。
