Wang Weijun, Du Lianghui, Li Jiang, Hu Mingzhe, Sun Changlin, Zhong Yajun, Zhao Gang, Li Zeren, Zhu Li-Guo, Yao Jianquan, Ling Furi
Opt Express. 2021 Apr 12;29(8):12712-12722. doi: 10.1364/OE.421820.
Active control of terahertz waves is a critical application for terahertz devices. Silicon is widely used in large-scale integrated circuit and optoelectronic devices, and also shows great potential in the terahertz field. In this paper, a p-Si hybrid metasurface device is proposed and its terahertz characteristics under avalanche breakdown effect is investigated. In the study, a plasmon-induced transparency (PIT) effect caused by the near-field coupling of the bright mode and the dark mode is observed in the transmission spectrum. Due to avalanche breakdown effect, the resonance of the PIT metamaterial disappears as the current increased. Carriers existed in the interface between the metasurface and substrate result to a dipole resonance suppression. When the current continues increasing, the maximal modulation depth can reach up to 99.9%, caused by the avalanche effect of p-Si. Experimental results demonstrate that the avalanche breakdown p-Si can achieve a performance modulation depth, bringing much more possibilities for terahertz devices.
太赫兹波的主动控制是太赫兹器件的关键应用。硅广泛应用于大规模集成电路和光电器件中，并且在太赫兹领域也显示出巨大潜力。本文提出了一种p型硅混合超表面器件，并研究了其在雪崩击穿效应下的太赫兹特性。在该研究中，在透射光谱中观察到由亮模式和暗模式的近场耦合引起的表面等离激元诱导透明（PIT）效应。由于雪崩击穿效应，随着电流增加，PIT超材料的共振消失。超表面与衬底界面处存在的载流子导致偶极子共振受到抑制。当电流持续增加时，由于p型硅的雪崩效应，最大调制深度可达99.9%。实验结果表明，雪崩击穿的p型硅可以实现性能调制深度，为太赫兹器件带来更多可能性。
