摘要
采用Au催化的固-液-气(VLS)方法制备了单晶Bi_2Se_3和Bi_2(Te_xSe_(1-x))_3纳米线,研究了单根纳米线器件的输运性质.在对单根Bi_2(Te_xSe_(1-x))3(x=0.26)纳米线的低温磁输运测试中观察到反弱局域效应,说明样品中存在较强的自旋-轨道耦合.结果表明,Te掺杂可以有效抑制体电导对输运过程的影响.通过对不同温度下的磁电导曲线进行拟合,得到了电子的退相干长度l_φ,l_φ从1.5 K时的389 nm减小至20 K时的39 nm,遵循l_φ∝T^(-0.96)指数变化规律.分析表明,在Te掺杂样品的输运过程中,电子-电子散射和电子-声子散射均起到了十分重要的作用.
Single-crystalline Bi2Se3 and Bi2 （TexSel_x ）z nanowires were synthesized via Au catalytic vapor-liquid- solid （VLS） growth method. Electronic properties of the surface states in individual Bi2 （TexSel_x ）3 （x = 0.26） nanowire were studied by low-temperature magnetotransport measurement. Weak antilocalization （WAL） effect was found, suggesting strong spin-orbit coupling in our samples. It is indicated that the bulk effect can be sup- pressed effectively by the Tellurium （Te） doping. By fitting the magnetoconductance curves at magnetic field up to 7 T measured at different temperatures, the extracted dephasing length / decreases from 389 nm at 1.5 K to 39 nm at 20 K, which can be well described by the power law l_φ∝T^（-0.96）. It can be reasonably deduced that both the elec- tron-electron scattering and the electron-phonon scattering play important roles in the Te-doped sample.
出处
《红外与毫米波学报》
SCIE
EI
CAS
CSCD
北大核心
2017年第3期270-275,共6页
Journal of Infrared and Millimeter Waves
基金
Supported by the National Natural Science Foundation of China(11304092,51371079,11305056,11304299,51602099)
the Open Foundation of Hubei Collaborative Innovation Center for High-efficiency Utilization of Solar Energy(HBSKFZD2014001,HBSKFM2014006,HBSKFM2014013,HBSKFM2014015)
