document: Topological insulators (TIs) are promising candidates of spintronics materials because of their robust helical surface states and the extremely strong spin–orbit interaction [1–3]. Initially, binary chalcogenides Bi2Te3, Sb2Te3 and Bi2Se3 have been identified as three-dimensional TIs by surface sensitive probes such as angle resolved photoemission spectroscopy and scanning tunneling microscopy/spectroscopy. Later, ternary chalcogenide (BixSb1−x)2Te3 [4,5], which has similar tetradymite structure to the parent compounds Bi2Te3 and Sb2Te3, was predicted by ab initio calculations and confirmed by ARPES measurements as a tunable topological insulator whose Fermi energy and carrier density can be adjusted via changing the Bi/Sb composition ratio with stable topological surface state for the entire composition range. Combined with magnetism or superconductivity, TIs have attracted great attention due to the rich variety of new physics and applications. The ferromagnetism in several transition metal (TM) doped TIs, which breaks the time-reversal symmetry, has been reported [6–13]. Ferromagnetism in TIs is important because the combination of magnetism with TIs makes a good platform to study fundamental physical phenomena, such as the quantum anomalous Hall effect [14–17], Majorana fermions [18], image magnetic monopole effect [19], and topological contributions to the Faraday and Kerr magneto-optical effect [20].
doc_bio_tags: B I B O O O O B I O O O O O O O O O O O B I O O B I B B O B O O O O O B O B I I O O B I I I O O O O O B I O O O O O O O O O O O B O B O O O B I I O O O B I O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B B O O O O O O O O O O O O O O O B O O B I B O B O O O O O O O O O B O B O O O O O O B O B O O O O O O B I I O O O O O B I O B I O B I I I O O O O O O O O O O O O
extractive_keyphrases: ab initio calculations angle resolved photoemission spectroscopy arpes measurements bi2se3 bi2te3 binary chalcogenides ferromagnetism fundamental physical phenomena hall effect image magnetic monopole effect magnetism majorana fermions sb2te3 spin–orbit interaction spintronics materials superconductivity surface sensitive probes ternary chalcogenide tis tm topological insulator topological insulators transition metal
abstractive_keyphrases: (bixsb1−x)2te3 changing the bi/sb composition ratio faraday and kerr magneto-optical effect scanning tunneling microscopy/spectroscopy