非金属原子掺杂扶手椅型砷烯纳米管的磁电子性质及调控

Magneto-electronic property and strain regulation for non-metal atom doped armchair arsenene nanotubes

诱发非磁材料磁性并灵活调控其磁电子性质对于研发高性能磁器件非常重要.基于密度泛函理论(DFT),系统研究了非金属原子X(X=B,N,P,Si,Se,Te)取代性掺杂扶手椅型砷烯纳米管AsANT的结构稳定性、磁电子性质、载流子迁移率以及应变对杂质管磁电子性质的调控效应.计算的结合能和形成能证明了杂质管AsANT-X的结构稳定性,可能在实验中实现.杂质管电子结构的计算表明AsANT-X(X=B,N,P)为无磁半导体,而AsANT-X(X=Si,Se,Te)表现为双极化磁性半导体,磁性源于杂质原子与As之间未配对电子的出现.此外,掺杂可以灵活调控AsANT的载流子迁移率到一个较宽的范围,并且呈现明显的载流子极性和自旋极性.特别是,应变可以导致AsANT-Si在双极化磁性半导体、半-半导体、磁金属和无磁金属之间的多磁相变过渡,这种在无磁态和高磁化态之间的转换可用于设计由应变控制的自旋极化输运的机械开关.本文研究为砷烯的应用提供了新途径.

For the development of high performance magnetic devices,inducing magnetism in non-magnetic materials and flexibly regulating their magneto-electronic properties are very important.According to the density functional theory(DFT),we systematically study the structural stability,magneto-electronic properties,carrier mobility and strain effect for each of armchair arsenene nanotubes doped with non-metallic atoms X(X=B,N,P,Si,Se,Te).The calculated binding energy and formation energy confirm that the geometric stability of AsANT-X is high.With non-metal doping,each of AsANT-X(X=B,N,P)acts as a non-magnetic semiconductor,while each of AsANT-X(X=Si,Se,Te)behaves as a bipolar magnetic semiconductor,caused by the unpaired electrons occurring between X and As.Furthermore,by doping,the carrier mobility of AsANTX can be flexibly moved to a wide region,and the carrier polarity and spin polarity in mobility can be observed as well.Especially,AsANT-Si can realize a transition among bipolar magnetic semiconductor,halfsemiconductor,magnetic metal,and non-magnetic metal by applying strain,which is useful for designing a mechanical switch to control spin-polarized transport that can reversibly work between magnetism and demagnetism only by applying strain.This study provides a new way for the application of arsenene.