Chiral topological excitons in a Chern band insulator

Article

关键词: TRANSITION-METAL DICHALCOGENIDES;    QUANTIZED HALL CONDUCTANCE;    CARBON NANOTUBES;    OPTICAL-SPECTRUM;    MONOLAYER WSE2;    QUANTUM DOTS;    EDGE STATES;    SEMICONDUCTOR;    LIGHT;    SPIN;   

DOI  :  10.1103/PhysRevB.96.161101

来源: SCIE

【 摘 要 】

A family of semiconductors called Chern band insulators are shown to host exciton bands with nonzero topological Chern integers and chiral exciton edge modes. Using a prototypical two-band Chern insulator model, we calculate a cross-correlation function to obtain the exciton bands and their Chern integers. The lowest exciton band acquires Chern integers such as +/- 1 and +/- 2 in the electronic Chern insulator phase. The nontrivial topology can be experimentally observed both by a nonlocal optoelectronic response of exciton edge modes and by a phase shift in the cross-correlation response due to the bulk mode. Our result suggests that magnetically doped HgTe, InAs/GaSb quantum wells, and (Bi,Sb)(2)Te-3 thin films are promising candidates for a platform of topological excitonics.

【 授权许可】

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