Details

Autor(en) / Beteiligte

• Wang, Z F
• Yao, Meng-Yu
• Ming, Wenmei
• Miao, Lin
• Zhu, Fengfeng
• Liu, Canhua
• Gao, C L
• Qian, Dong
• Jia, Jin-Feng
• Liu, Feng

Titel

Creation of helical Dirac fermions by interfacing two gapped systems of ordinary fermions

Ist Teil von

• Nature communications, 2013-01, Vol.4 (1), p.1384-1384, Article 1384

Ort / Verlag

England: Nature Publishing Group

Erscheinungsjahr

2013

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Topological insulators are a unique class of materials characterized by a Dirac cone state of helical Dirac fermions in the middle of a bulk gap. When the thickness of a three-dimensional topological insulator is reduced, however, the interaction between opposing surface states opens a gap that removes the helical Dirac cone, converting the material back to a normal system of ordinary fermions. Here we demonstrate, using density function theory calculations and experiments, that it is possible to create helical Dirac fermion state by interfacing two gapped films-a single bilayer Bi grown on a single quintuple layer Bi(2)Se(3) or Bi(2)Te(3). These extrinsic helical Dirac fermions emerge in predominantly Bi bilayer states, which are created by a giant Rashba effect with a coupling constant of ~4 eV·Å due to interfacial charge transfer. Our results suggest that this approach is a promising means to engineer topological insulator states on non-metallic surfaces.