近日，首都师范大学的周庆莉及其研究小组与中国科学院物理研究所的葛琛等人合作并取得一项新进展。经过不懈努力，他们研制出碲基全二维异质结衬底场感应的高性能太赫兹调制器。相关研究成果已于2024年3月5日在国际知名学术期刊《光：科学与应用》上发表。

本文介绍了具有独特结构的二维碲(Te)纳米膜作为一类新型光控太赫兹调制器，并证明其集成异质结可以成功地将器件性能提高到现有全二维宽带调制器的最佳适用水平。进一步的光响应测量证实了堆叠顺序的显著影响。

研究人员首先通过第一性原理计算阐明了衬底感应电场的方向，揭示了与电荷转移和层间激子复合相关的光激发载流子动力学中不寻常的相互作用机制。这推动了碲纳米材料在高性能太赫兹光电子学中的基础和应用研究。

据悉，高性能有源太赫兹调制器作为下一代通信技术不可缺少的核心部件，具有十分重要的意义。然而，它们目前受到调制深度和速度之间权衡的影响。

附：英文原文

Title: High-performance terahertz modulators induced by substrate field in Te-based all-2D heterojunctions

Author: Zhang, Pujing, Liang, Qihang, Zhou, Qingli, Chen, Jinyu, Li, Menglei, Deng, Yuwang, Liang, Wanlin, Zhang, Liangliang, Zhang, Qinghua, Gu, Lin, Ge, Chen, Jin, Kui-juan, Zhang, Cunlin, Yang, Guozhen

Issue&Volume: 2024-03-05

Abstract: High-performance active terahertz modulators as the indispensable core components are of great importance for the next generation communication technology. However, they currently suffer from the tradeoff between modulation depth and speed. Here, we introduce two-dimensional (2D) tellurium (Te) nanofilms with the unique structure as a new class of optically controlled terahertz modulators and demonstrate their integrated heterojunctions can successfully improve the device performances to the optimal and applicable levels among the existing all-2D broadband modulators. Further photoresponse measurements confirm the significant impact of the stacking order. We first clarify the direction of the substrate-induced electric field through first-principles calculations and uncover the unusual interaction mechanism in the photoexcited carrier dynamics associated with the charge transfer and interlayer exciton recombination. This advances the fundamental and applicative research of Te nanomaterials in high-performance terahertz optoelectronics.

DOI: 10.1038/s41377-024-01393-6

Source: https://www.nature.com/articles/s41377-024-01393-6