Electrically controlled ferromagnetism in 2-dimensional semiconductors

二维半导体中的电控铁磁性

• 批准号: 437096397
• 负责人: Privatdozent Dr. Michael Martins
• 金额: --
• 依托单位: Laboratoire de Physique de Solides - UMR 8502
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/437096397?language=en
• 关键词: Electrically; controlled; ferromagnetism; dimensional; semiconductors

The DIMAG project is dedicated to establishing a new type of 2D magnetic materials, which not only exhibits a fundamentally new type of ferromagnetic behavior, but also has optimal characteristics for spintronics applications. This 36-month project, brings together 5 academic laboratories: the Laboratory for Semiconductor Physics (KU Leuven, Belgium), the Institute for Nuclear and Radiation Physics (KU Leuven, Belgium), the Physics Department of the Hamburg University (Germany), the Laboratoire de Physique des Solides (CNRS, France), and Laboratory of Quantum Optics of the University of Nova Gorica (Slovenia). Each group brings highly specialized expertise, and advanced experimental and density functional theory methods that are key to achieving the goals of DIMAG, which in turn are beyond the state of the art. The general goal of DIMAG is to induce and study Stoner-type ferromagnetism in 2D semiconductors exhibiting a Van Hove singularity in the density of states (DOS), as predicted for GaSe, InSe, and SnO. First we will develop the synthesis of high-quality 2D materials with a controlled number of layers, by exfoliation from commercially available single crystals, as well as by molecular beam epitaxy. We will optimize the number of layers in order to maximize the DOS at the Van Hove singularity, as a compromise between low number of layers and high layer quality. In parallel, we will develop the control of the Fermi level in the vicinity of the Van Hove singularity (by acceptor doping and electrical gating), which is predicted to result in a Stoner instability and induce a ferromagnetic state. We will study these effects in detail: scanning tunnelling microscopy and spectroscopy to probe structural, electronic and magnetic properties at the atomic scale; angle resolved photoemission spectroscopy and inverse photoemission spectroscopy (static and time-resolved) to fully characterize the electronic structure below and above the Fermi level; X-ray magnetic circular dichroism and magneto-optical Kerr effect to establish the intrinsic origin of the ferromagnetic behavior. Based on this detailed understanding, we will optimize the materials synthesis, aiming to: (i) increase the ordering temperature and the carrier spin-polarization up to the highest achievable values; (ii) reversibly switch between ferromagnetic and non-ferromagnetic states with voltage bias. The DIMAG project directly addresses key goals of the Flagship work program, namely division 1 (Enabling Science and Materials), work packages 1 and 2 (WP1 - Enabling research; WP2 - Spintronics). In addition to its underlying fundamental nature, the project is highly application-oriented, as it aims to deliver new functionality that is device-compatible. Taking the Flagship’s WP1 and WP2 beyond graphene, into new 2D materials, DIMAG will have a tremendous impact, opening a broad new area of fundamental and applied research on new materials with device-compatible properties and functionality.

DIMAG项目致力于建立一种新型的2D磁性材料，该材料不仅表现出根本上新型的铁磁行为，而且还具有用于Spintronics应用的最佳特征。这个36个月的项目汇集了5个学术实验室：半导体物理学实验室（比利时鲁文），核与辐射物理学研究所（比利时库武文），汉堡大学物理系，德国大学（德国），Laborato de solique des solique des solique（CNR），QUNICE（CNR）和实验室，QUANS，FRASE，FRASE，FRASE，FRASE，FRANE，FRASE，FRANE，FRASE，FRASE的实验室， （斯洛文尼亚）。每个小组都带来了高度专业化的专业知识，以及高级实验和密度功能理论方法，这些方法是实现DIMAG目标的关键，而DIMAG的目标又超出了艺术的状态。 DIMAG的一般目标是在2D半导体中诱导和研究Stoner型铁磁性，如GASE，INSE和SNO所预测的，在状态密度（DOS）中表现出范霍夫的奇异性（DOS）。首先，我们将通过从市售的单晶以及分子束发作中剥落具有控制层的高质量2D材料的合成。我们将优化层的数量，以最大程度地提高范霍夫（Van Hove）奇异性的DOS，这是在较少的层和高层质量之间的折衷方案。同时，我们将在van霍夫奇异性附近（通过受体掺杂和电控）中建立对费米水平的控制，这预计会导致僵硬的不稳定性并诱导铁磁状态。我们将详细研究这些效果：将隧道显微镜和光谱扫描以在原子尺度探测结构，电子和磁性。角度分辨光发射光谱和逆光发射光谱（静态和时间分辨），以充分表征费米水平下方和更高的电子结构； X射线磁性圆形二色性和磁光kerr效应，以建立铁磁行为的内在起源。基于这种详细的理解，我们将优化材料合成，目的是：（i）将订购温度和载体自旋化度提高到最高可实现的值； （ii）在具有电压偏置的铁磁和非铁磁状态之间可逆切换。 DIMAG项目直接解决了旗舰工作计划的关键目标，即1分区（启用科学和材料），工作包1和2（WP1-启用研究； WP2 -Spintronics）。除了其潜在的基本性质外，该项目旨在提供与设备兼容的新功能，因此该项目具有高度的面向应用程序。 DIMAG将旗舰店的WP1和WP2超出石墨烯之外，将产生巨大的影响，为具有兼容设备兼容的属性和功能的新材料开辟了广泛的基本和应用研究。