1202.4957 (Huiwen Ji et al.)

Bulk Intergrowth of a Topological Insulator with a Room Temperature
Ferromagnet    [PDF]

Huiwen Ji, J. M. Allred, Ni Ni, Jing Tao, M. Neupane, A. Wray, S. Xu, M. Z. Hasan, R. J. Cava

We demonstrate that the layered room temperature ferromagnet Fe7Se8 and the
topological insulator Bi2Se3 form crystallographically oriented bulk composite
intergrowth crystals. The morphology of the intergrowth in real space and
reciprocal space is described. Critically, the basal planes of Bi2Se3 and
Fe7Se8 are parallel and hence the good cleavage inherent in the bulk phases is
retained. The intergrowth is on the micron scale. Both phases in the
intergrowth crystals display their intrinsic bulk properties: the
ferromagnetism of the Fe7Se8 is anisotropic, with magnetization easy axis in
the plane of the crystals, and ARPES characterization shows that the
topological surface states remain present on the Bi2Se3. Analogous behavior is
found for what has been called "Fe-doped Bi2Se3."

View original: http://arxiv.org/abs/1202.4957