Šiškins Makars, Lee Martin, Mañas-Valero Samuel, Coronado Eugenio, Blanter Yaroslav M, van der Zant Herre S J, Steeneken Peter G
Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ, Delft, The Netherlands.
Instituto de Ciencia Molecular (ICMol), Universitat de València, c/Catedrático José Beltrán 2, 46980, Paterna, Spain.
Nat Commun. 2020 Jun 1;11(1):2698. doi: 10.1038/s41467-020-16430-2.
The reduced dimensionality of two-dimensional (2D) materials results in characteristic types of magnetically and electronically ordered phases. However, only few methods are available to study this order, in particular in ultrathin insulating antiferromagnets that couple weakly to magnetic and electronic probes. Here, we demonstrate that phase transitions in thin membranes of 2D antiferromagnetic FePS, MnPS and NiPS can be probed mechanically via the temperature-dependent resonance frequency and quality factor. The observed relation between mechanical motion and antiferromagnetic order is shown to be mediated by the specific heat and reveals a strong dependence of the Néel temperature of FePS on electrostatically induced strain. The methodology is not restricted to magnetic order, as we demonstrate by probing an electronic charge-density-wave phase in 2H-TaS. It thus offers the potential to characterize phase transitions in a wide variety of materials, including those that are antiferromagnetic, insulating or so thin that conventional bulk characterization methods become unsuitable.
二维（2D）材料的低维特性导致了具有磁序和电子序的特征相类型。然而，研究这种序的方法很少，特别是在与磁探针和电子探针弱耦合的超薄绝缘反铁磁体中。在这里，我们证明二维反铁磁体FePS、MnPS和NiPS薄膜中的相变可以通过与温度相关的共振频率和品质因数进行机械探测。观察到的机械运动与反铁磁序之间的关系表明是由比热介导的，并且揭示了FePS的奈尔温度对静电诱导应变的强烈依赖性。我们通过探测2H-TaS中的电荷密度波相证明，该方法不仅限于磁序。因此，它有可能表征各种材料中的相变，包括那些反铁磁、绝缘或太薄以至于传统体相表征方法不适用的材料。
