MoS2势垒层磁性隧道结的温度-偏压特性研究

Study on Temperature-Bias Characteristic of Magnetic Tunnel Junctions with MoS2 Barrier

摘要:

MoS₂是一种具有特殊能带结构的二维半导体材料,当层数较少时,其带隙会随层数显著减小。因此,基于MoS₂势垒层的磁性隧道结会展现出更丰富的物理特性。文章通过理论计算分别得到了单层、双层、三层以及五层MoS₂势垒层磁性隧道结的温度-偏压相图,研究了铁磁电极半交换劈裂能对相图特性的影响。计算结果表明:单层和三层MoS₂势垒层磁性隧道结适合应用于低温器件中。其中,单层MoS₂势垒层磁性隧道结在高功率工作环境下具有优异的性能。双层MoS₂势垒层磁性隧道结的优化区域位于室温和低偏压区,因此适用于信息存储领域。五层MoS₂势垒层磁性隧道结可通过调节铁磁电极参数使其工作在较宽的功率范围内。上述研究结果为MoS₂势垒层磁性隧道结的应用奠定了坚实的理论基础。

Abstract:

MoS₂ is a kind of two-dimensional semiconductor material with unique band structure. For few-layer MoS₂, the band gap decreases significantly with the number of layers. Accordingly, the magnetic tunnel junctions (MTJs) with MoS₂ barrier will show abundant and various physical properties. In this paper, the temperature-bias phase diagrams are calculated, respectively, for MTJs with single-layer MoS₂, double-layer MoS₂, three-layer MoS₂ and five-layer MoS₂ barrier under different half the exchange splitting of the ferromagnetic electrodes. The calculations show that, the MTJs with single-layer and three-layer MoS₂ barrier is suitable to be applied at low temperature. In particular, the MTJs with single-layer MoS₂ barrier possess excellent performance at high bias. The optimized region of MTJs with double-layer MoS₂ barrier is located at room temperature and low bias. Therefore, they are favorable for the application of information storage. Through regulating the parameter of the ferromagnetic electrodes, the MTJs with five-layer MoS₂ barrier can work throughout a wide power range. The above results lay a solid theoretical foundation for the application of MTJs with MoS₂ barrier.