Quantum Dots Formed in Three-dimensional Dirac Semimetal Cd3As2 Nanowires
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2018-02-23 |
| Journal | Nano Letters |
| Authors | Minkyung Jung, Kenji Yoshida, Kidong Park, Xiao-Xiao Zhang, Can Yesilyurt |
| Institutions | National University of Singapore, RIKEN Center for Emergent Matter Science |
| Citations | 20 |
Abstract
Section titled āAbstractāWe demonstrate quantum dot (QD) formation in three-dimensional Dirac semimetal Cd<sub>3</sub>As<sub>2</sub> nanowires using two electrostatically tuned p-n junctions with a gate and magnetic fields. The linear conductance measured as a function of gate voltage under high magnetic fields is strongly suppressed at the Dirac point close to zero conductance, showing strong conductance oscillations. Remarkably, in this regime, the Cd<sub>3</sub>As<sub>2</sub> nanowire device exhibits Coulomb diamond features, indicating that a clean single QD forms in the Dirac semimetal nanowire. Our results show that a p-type QD can be formed between two n-type leads underneath metal contacts in the nanowire by applying gate voltages under strong magnetic fields. Analysis of the quantum confinement in the gapless band structure confirms that p-n junctions formed between the p-type QD and two neighboring n-type leads under high magnetic fields behave as resistive tunnel barriers due to cyclotron motion, resulting in the suppression of Klein tunneling. The p-type QD with magnetic field-induced confinement shows a single hole filling. Our results will open up a route to quantum devices such as QDs or quantum point contacts based on Dirac and Weyl semimetals.