VanGennep D, Jackson D E, Graf D, Berger H, Hamlin J J
Department of Physics, University of Florida, Gainesville, FL 32611, United States of America.
J Phys Condens Matter. 2017 Jul 26;29(29):295702. doi: 10.1088/1361-648X/aa73b7. Epub 2017 May 17.
We report measurements of Shubnikov-de Haas oscillations in the giant Rashba semiconductor BiTeCl under applied pressures up to ∼2.5 GPa. We observe two distinct oscillation frequencies, corresponding to the Rashba-split inner and outer Fermi surfaces. BiTeCl has a conduction band bottom that is split into two sub-bands due to the strong Rashba coupling, resulting in two spin-polarized conduction bands as well as a Dirac point. Our results suggest that the chemical potential lies above this Dirac point, giving rise to two Fermi surfaces. We use a simple two-band model to understand the pressure dependence of our sample parameters. Comparing our results on BiTeCl to previous results on BiTeI, we observe similar trends in both the chemical potential and the Rashba splitting with pressure.
我们报告了在高达约2.5 GPa的外加压力下，对巨Rashba半导体BiTeCl中舒布尼科夫-德哈斯振荡的测量结果。我们观察到两个不同的振荡频率，分别对应于Rashba分裂的内、外费米面。由于强Rashba耦合，BiTeCl的导带底分裂为两个子带，从而产生两个自旋极化的导带以及一个狄拉克点。我们的结果表明，化学势位于该狄拉克点之上，从而产生两个费米面。我们使用一个简单的双带模型来理解我们样品参数的压力依赖性。将我们在BiTeCl上的结果与之前在BiTeI上的结果进行比较，我们观察到化学势和Rashba分裂随压力变化呈现出相似的趋势。
