Lu Hua, Li Yangwu, Yue Zengji, Mao Dong, Zhao Jianlin
Opt Express. 2020 Oct 12;28(21):31893-31903. doi: 10.1364/OE.397753.
As newly emerging nanomaterials, topological insulators with unique conducting surface states that are protected by time-reversal symmetry present excellent prospects in electronics and photonics. The active control of light absorption in topological insulators are essential for the achievement of novel optoelectronic devices. Herein, we investigate the controllable light absorption of topological insulators in Tamm plasmon multilayer systems composed of a BiSbTeSe (BSTS) film and a dielectric Bragg mirror with a graphene-involved defect layer. The results show that an ultranarrow electromagnetically induced transparency (EIT)-like window can be generated in the broad absorption spectrum. Based on the EIT-like effect, the Tamm plasmon enhanced light absorption of topological insulators can be dynamically tuned by adjusting the gate voltage on graphene in the defect layer. These results will pave a new avenue for the realization of topological insulator-based active optoelectronic functionalities, for instance light modulation and switching.
作为新兴的纳米材料，具有受时间反演对称性保护的独特导电表面态的拓扑绝缘体在电子学和光子学领域展现出优异的前景。对拓扑绝缘体中光吸收的主动控制对于实现新型光电器件至关重要。在此，我们研究了由BiSbTeSe（BSTS）薄膜和具有含石墨烯缺陷层的介质布拉格镜组成的Tamm等离子体多层系统中拓扑绝缘体的可控光吸收。结果表明，在宽吸收光谱中可产生超窄的类电磁诱导透明（EIT）窗口。基于类EIT效应，通过调节缺陷层中石墨烯上的栅极电压，可以动态调控拓扑绝缘体的Tamm等离子体增强光吸收。这些结果将为实现基于拓扑绝缘体的有源光电子功能（如光调制和光开关）开辟一条新途径。
