Layer-number-parity-dependent abnormal magnetic ordering in few-layer CrI3 on N-face AlN substrate

Description

Chen and co-authors demonstrate, in 2026, that a polar aluminum nitride substrate can program unusual magnetic states in few-layer chromium triiodide, a two-dimensional magnet. On ordinary substrates, odd-layer samples of this material flip between simple states. Grown on single-crystal nitrogen-face AlN and protected under hexagonal boron nitride, five-layer samples instead stepped through a sequence of magnetic multistates. The switching happened as the field swept from 3 tesla down to negative 3 tesla.

The dichroism signal evolved through states labeled plus 5, minus 1, plus 1, and minus 5, where each unit corresponds to one monolayer's magnetic moment. First-principles calculations attribute the effect to interfacial hole doping from the polar substrate, which reconfigures the ground state into a ferrimagnetic order and differentiates coupling between surface and interior layers. The substrate raised the magnetic ordering temperature by about 5.3 percent compared with silicon dioxide supports, a step toward ultrathin magnetic devices.

Catalog record

Source: https://europepmc.org/articles/PMC13396473