High-performance active terahertz modulators are crucial for next-generation communication technology, but current designs struggle with balancing modulation depth and speed. This research introduces two-dimensional (2D) tellurium (Te) nanofilms as optically controlled terahertz modulators, demonstrating that their integrated heterojunctions significantly improve device performance. Photoresponse measurements highlight the importance of stacking order. First-principles calculations clarify the substrate-induced electric field and its role in charge transfer and interlayer exciton recombination, advancing the use of Te nanomaterials in terahertz optoelectronics.
