Electronic phase transitions of bismuth under strain from relativistic self-consistent GW calculations
Electronic phase transitions of bismuth under strain from relativistic self-consistent GW calculations
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DOI：
10.1103/physrevb.91.125129
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发表时间：
2015-03-18
影响因子：
3.7
通讯作者：
Bluegel, Stefan
中科院分区：
文献类型：
--
作者：
Aguilera, Irene;Friedrich, Christoph;Bluegel, Stefan
我们用准粒子自洽GW(QSGW)方法计算了半金属块体的结构。我们超越了传统的QSGW方法，在整个自洽循环中考虑了自旋-轨道耦合。与标准密度泛函理论(DFT)相比，这种方法极大地改进了对电子和空穴口袋的描述，使其与实验符合得很好。我们用这个相对论的QSGW方法研究了应变下Bi半金属到半导体和平凡到拓扑的转变。DFT预测，这种转变需要一个非物理上的大应变。通过电子结构的相对论QSGW描述，仅0.3%的面内拉伸应变和0.4%的压缩应变就足以分别引起半金属到半导体和平凡到拓扑的相变。因此，所需的应变进入了可能在实验中实现的区域，这为探索纯铋的块状拓扑行为打开了可能性。
We present quasiparticle self-consistent GW (QSGW) calculations of semimetallic bulk Bi. We go beyond the conventional QSGW method by including the spin-orbit coupling throughout the self-consistency cycle. This approach improves the description of the electron and the hole pockets considerably with respect to standard density functional theory (DFT), leading to excellent agreement with experiment. We employ this relativistic QSGW approach to conduct a study of the semimetal-to-semiconductor and the trivial-to-topological transitions that Bi experiences under strain. DFT predicts that an unphysically large strain is needed for such transitions. We show, by means of the relativistic QSGW description of the electronic structure, that an in-plane tensile strain of only 0.3% and a compressive strain of 0.4% are sufficient to cause the semimetal-to-semiconductor and the trivial-to-topological phase transitions, respectively. Thus, the required strain moves into a regime that is likely to be realizable in experiment, which opens up the possibility to explore bulklike topological behavior of pure Bi.