...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Physical review >Giant proximity exchange and valley splitting in transition metal dichalcogenide/hBN/(Co, Ni) heterostructures
【24h】

Giant proximity exchange and valley splitting in transition metal dichalcogenide/hBN/(Co, Ni) heterostructures

机译：过渡金属二硫化氢/ hBN /（Co，Ni）异质结构中的巨大邻近交换和峰谷分裂

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We investigate the proximity-induced exchange coupling in transition-metal dichalcogenides (TMDCs). originating from spin injector geometries composed of hexagonal boron-nitride (hBN) and ferromagnetic (FM) cobalt (Co) or nickel (Ni), from first principles. We employ a minimal tight-binding Hamiltonian that captures the low energy bands of the TMDCs around K and K' valleys, to extract orbital, spin-orbit, and exchange parameters. The TMDC/hBN/FM heterostructure calculations show that due to the hBN buffer layer, the band structure of the TMDC is preserved, with an additional proximity-induced exchange splitting in the bands. We extract proximity exchange parameters in the 1-10 meV range, depending on the FM. The combination of proximity-induced exchange and intrinsic spin-orbit coupling (SOC) of the TMDCs. leads to a valley polarization, translating into magnetic exchange fields of tens of Tesla. The extracted parameters are useful for subsequent exciton calculations of TMDCs in the presence of a /hBN/FM spin injector. Our calculated absorption spectra show large splittings for the exciton peaks; in the case of MoS_2/hBN/Co we find a value of about 8 meV, corresponding to about 50 T external magnetic field in bare TMDCs. The reason lies in the band structure, where a hybridization with Co d orbitals causes a giant valence band exchange splitting of more than 10 meV. Structures with Ni do not show any d level hybridization features, but still sizable proximity exchange and exciton peak splittings of around 2 meV are present in the TMDCs.
机译：我们调查过渡金属二卤化物（TMDCs）中的邻近感应交换耦合。源自第一个原理的旋转喷射器几何形状，该几何形状由六方氮化硼（hBN）和铁磁（FM）钴（Co）或镍（Ni）组成。我们采用最小紧束缚哈密顿量，该量捕获K和K'谷周围TMDC的低能带，以提取轨道，自旋轨道和交换参数。 TMDC / hBN / FM异质结构计算表明，由于hBN缓冲层，保留了TMDC的能带结构，并在该能带中进行了额外的邻近感应交换。我们根据FM提取1-10 meV范围内的邻近交换参数。 TMDC的邻近感应交换和固有自旋轨道耦合（SOC）的组合。导致谷极极化，转化为数十特斯拉的磁场。在存在/ hBN / FM自旋注入器的情况下，提取的参数可用于TMDC的后续激子计算。我们计算出的吸收光谱显示出激子峰的大分裂;对于MoS_2 / hBN / Co，我们发现大约为8 meV，相当于裸露的TMDC中大约50 T的外部磁场。原因在于能带结构，其中与Co d轨道的杂交导致超过10 meV的巨大价带交换分裂。具有Ni的结构未显示任何d级杂交特征，但TMDC中仍存在相当大的邻近交换和2 meV左右的激子峰分裂。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号