Ghosh Atish, Kar Moumita, Majumder Chiranjib, Sarkar Pranab
Department of Chemistry, Visva-Bharati University, Santiniketan- 731235, India.
Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India.
Phys Chem Chem Phys. 2021 Jan 21;23(2):1127-1138. doi: 10.1039/d0cp05221c.
Half metallic materials with intrinsic ferromagnetism are identified as the pillar of next generation spintronic devices. In search of new low-dimensional materials with these excellent properties, herein we systematically study the electronic and magnetic properties of edge dependent (armchair (ac) and zigzag (zz)) vanadium nitride nanoribbons (VNNRs) using density functional theory (DFT) based calculations. Both the ac and zz VNNRs show robust ferromagnetism and extensive half-metallicity with large band gaps (3.9-4.3 eV for ac and 2.5-3.0 eV for zz VNNRs) for the down spin channel. Interestingly, even with the application of uniaxial strain (both tensile and compressive) along the axis of the ribbons, VNNRs retain their extensive half metallicity with a large spin band gap and robust ferromagnetic behavior. Spin dependent electronic transport reveals the 100% spin filtering efficiency of nanoribbons, in both the free state and under applied strain, which support the robust half metallicity of VNNRs. Our study of VNNRs on a MoS2 substrate also shows half metallicity along with high stability, indicating the usage of MoS2 as a substrate for the synthesis of VNNRs. All these results guide the potential application of VNNRs in spintronic devices.
具有本征铁磁性的半金属材料被视为下一代自旋电子器件的支柱。为了寻找具有这些优异性能的新型低维材料，在此我们使用基于密度泛函理论（DFT）的计算方法，系统地研究了边缘依赖型（扶手椅型（ac）和锯齿型（zz））氮化钒纳米带（VNNRs）的电子和磁性特性。ac和zz VNNRs均表现出强大的铁磁性和广泛的半金属性，其向下自旋通道具有较大的带隙（ac为3.9 - 4.3 eV，zz VNNRs为2.5 - 3.0 eV）。有趣的是，即使沿着纳米带的轴施加单轴应变（拉伸和压缩），VNNRs仍保持其广泛的半金属性，具有较大的自旋带隙和强大的铁磁行为。自旋相关的电子输运揭示了纳米带在自由状态和施加应变下均具有100%的自旋过滤效率，这支持了VNNRs强大的半金属性。我们对VNNRs在MoS2衬底上的研究还表明其具有半金属性以及高稳定性，这表明MoS2可作为合成VNNRs的衬底。所有这些结果为VNNRs在自旋电子器件中的潜在应用提供了指导。
