Aalto University, Low Temperature Laboratory, Department of Applied Physics, Espoo, Finland.
Racah Institute of Physics, Hebrew University of Jerusalem, Givat Ram, Jerusalem, 91904, Israel.
Sci Rep. 2018 Jan 12;8(1):594. doi: 10.1038/s41598-017-18959-7.
We have investigated tunneling current through a suspended graphene Corbino disk in high magnetic fields at the Dirac point, i.e. at filling factor ν = 0. At the onset of the dielectric breakdown the current through the disk grows exponentially before ohmic behaviour, but in a manner distinct from thermal activation. We find that Zener tunneling between Landau sublevels dominates, facilitated by tilting of the source-drain bias potential. According to our analytic modelling, the Zener tunneling is strongly affected by the gyrotropic force (Lorentz force) due to the high magnetic field.
我们研究了在狄拉克点（即填充因子 ν = 0）处的强磁场中通过悬空石墨烯科里诺盘的隧道电流。在介电击穿开始时，圆盘中的电流在欧姆行为之前呈指数增长，但方式与热激活不同。我们发现，朗道子能级之间的齐纳隧道主导了这一过程，这得益于源漏偏压的倾斜。根据我们的分析模型，由于强磁场，陀螺力（洛伦兹力）强烈影响齐纳隧道。
