Cheng Ting, Lang Haifeng, Li Zhenzhu, Liu Zhongfan, Liu Zhirong
College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Phys Chem Chem Phys. 2017 Sep 13;19(35):23942-23950. doi: 10.1039/c7cp03736h.
We have theoretically investigated the intrinsic carrier mobility in semimetals with tilted Dirac cones under both longitudinal and transverse acoustic phonon scattering. An analytical formula for the carrier mobility was obtained. It shows that tilting significantly reduces the mobility. The theory was then applied to 8B-Pmmn borophene and borophane (fully hydrogenated borophene), both of which have tilted Dirac cones. The predicted carrier mobilities in 8B-Pmmn borophene at room temperature are 14.8 × 10 and 28.4 × 10 cm V s along the x and y directions, respectively, both of which are higher than that in graphene. For borophane, despite its superhigh Fermi velocity, the carrier mobility is lower than that in 8B-Pmmn owing to its smaller elastic constant under shear strain.
我们从理论上研究了具有倾斜狄拉克锥的半金属在纵向和横向声学声子散射下的本征载流子迁移率。得到了载流子迁移率的解析公式。结果表明，倾斜显著降低了迁移率。该理论随后被应用于8B-Pmmn硼烯和硼烷（完全氢化的硼烯），它们都具有倾斜的狄拉克锥。预测在室温下，8B-Pmmn硼烯中沿x和y方向的载流子迁移率分别为14.8×10和28.4×10 cm² V⁻¹ s⁻¹，均高于石墨烯中的迁移率。对于硼烷，尽管其费米速度超高，但由于其在剪切应变下较小的弹性常数，其载流子迁移率低于8B-Pmmn硼烯中的迁移率。
