The transport properties of Cl-decorated arsenene controlled by electric field

The large contact resistance is an insurmountable problem for the Schottky contact between the semiconducting two-dimensional channel material and the metal electrode. One solution to the Schottky contact issue is to decrease the contact resistance. Here, by using the first-principles calculations combined with the non-equilibrium Green's function technique, we find that when monolayer arsenene is covalently bonded with chlorine adatoms, it can transformfrom the intrinsic semiconductor to metal, which greatly improves its conductivity. Moreover, in the double-layer structure, the Cl adatoms can hop from one layer to the other by applying a vertical electric field. Their interlayer translation can turn arsenene and metallic electrodes from Schottky contact to Ohmic contact, then the resistance is greatly reduced, producing significant switching effects. The highest on/off ratio is as large as 638 at zero bias voltage, which can be utilized as nonvolatile high-density memory and logic operation devices based on arsenene homojunction.