Charge transport in pn and npn junctions of silicene

TL;DR

This paper studies charge transport in silicene pn and npn junctions, revealing unique conductance behaviors related to topological phases and electric field-induced phase transitions, with potential applications in nanoelectronics.

Contribution

It demonstrates how conductance in silicene junctions depends on topological phases and electric fields, highlighting quantized conductance and phase transition effects.

Findings

Conductance varies with gate voltage and topological phase.

Conductance is suppressed or quantized depending on phase configuration.

Electric field induces topological phase transition affecting transport.

Abstract

We investigate charge transport of pn and npn junctions made from silicene, Si analogue of graphene. The conductance shows the distinct gate-voltage dependences peculiar to the topological and non-topological phases, where the topological phase transition is caused by external electric field. Namely, the conductance is suppressed in the np regime when the both sides are topological, while in the nn regime when one side is topological and the other side is non-topological. Furthermore, we find that the conductance is almost quantized to be 0, 1 and 2. Our findings will open a new way to nanoelectronics based on silicene.