Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

Transition-metal rich semiconductor nanostructures driven by spinodal decomposition are drawing considerable attention due to wide prospects of functionalization [1]. However, the complexity of the magnetic cations aggregation (e.g. the competition between p-d hybridization driven attractive force between magnetic cation, entropy terms, and kinetic barriers) hinders obtaining nano-clusters with the desirable structure. Here, a 1-dimensional (In,Fe)As mixed Konbu phase is tailoring by employing ion implantation and subsequent pulsed laser melting (shown in Fig. 1). These Fe-rich nano-columns are fully commensurate with the InAs host lattice and exhibit an isotropic super-paramagnetic behavior. The XAS/XMCD result shows that Fe atoms with valence +2 and +3 are co-existing and both are spin-polarized. Therefore, it is likely that the magnetism in these Fe-rich nano-columns can be provided via the double exchange mechanism as previously described for the Cr-rich phase in (Zn, Cr)Te [2]. However, it still remains to be clarified why these distinctive structures are formed only in InAs: Fe, but not in other III-Mn-V systems obtained by the same method.

[1]. T. Dietl, et al., Rev. Mod. Phys., 87, 1311-1377 (2015)
[2]. K. Kanazawa, et al., Nanoscale, 6, 14667-14673 (2014)