Suppressed Fermi Level Pinning and Wide-Range Tunable Schottky Barrier in CrX 3 (X = I, Br)/2D Metal Contacts.

CrX 3 (X = I, Br) monolayers exhibit outstanding performance in spintronic devices. However, the Schottky barrier at the CrX 3 /electrode interface severely impedes the charge injection efficiency. Herein, we propose two-dimensional (2D) metals as electrodes to form van der Waals (vdW) contact with CrX 3 monolayers and systematically explore the contact properties of CrX 3 /metal by density functional theory (DFT) calculations. The results demonstrate that the strongly suppressed Fermi level pinning (FLP) effect and the wide-range tunable Schottky barrier can be achieved in CrX 3 /metal contacts. Specifically, the n-type and the p-type Schottky contacts can be realized in CrX 3 /metal contacts by choosing 2D metal electrodes with different work functions. Importantly, the pinning factors for CrX 3 /metal contacts are exceptionally larger than other commonly studied 2D semiconductors, indicating the strongly suppressed FLP in CrX 3 /metal contacts, which leads to the wide-range tunable Schottky barrier. Our findings provide guidance to the choice of electrodes and promote the development of CrX 3 -based spin devices.