Abstract
We report a study of enhancing the magnetic ordering in a model magnetically doped topological insulator (TI), Bi2–xCrxSe3, via the proximity effect using a high-TC ferrimagnetic insulator Y3Fe5O12. The FMI provides the TI with a source of exchange interaction yet without removing the nontrivial surface state. By performing the elemental specific X-ray magnetic circular dichroism (XMCD) measurements, we have unequivocally observed an enhanced TC of 50 K in this magnetically doped TI/FMI heterostructure. We have also found a larger (6.6 nm at 30 K) but faster decreasing (by 80% from 30 to 50 K) penetration depth compared to that of diluted ferromagnetic semiconductors (DMSs), which could indicate a novel mechanism for the interaction between FMIs and the nontrivial TIs surface.
| Original language | English |
|---|---|
| Pages (from-to) | 764–769 |
| Number of pages | 6 |
| Journal | Nano Letters |
| Volume | 15 |
| Issue number | 1 |
| Early online date | 22 Dec 2014 |
| DOIs | |
| Publication status | Published - 14 Jan 2015 |