Terahertz multi-level nonvolatile optically rewritable encryption memory based on chalcogenide phase-change materials
Shoujun Zhang, Xieyu Chen, Kuan Liu, Haiyang Li, Yuanhao Lang, Jie Han, Qingwei Wang, Yongchang Lu, Jianming Dai, Tun Cao, Zhen Tian
Abstract
(GST). By tuning the laser fluence irradiated on GST, we experimentally achieve multiple intermediate states and large-area amorphization with a diameter of centimeter-level in the THz regime. Our memory unit features a high operating speed of up to 4 ns, excellent reproducibility, and long-term stability. Utilizing this approach, hexadecimal coding information memories are implemented, and multiple writing-erasing tests are successfully carried out in the same active area. Finally, terahertz photoprint memory is demonstrated, verifying the feasibility of lithography-free devices. The demonstration suggests a practical way to protect and store information and paves a new avenue toward nonvolatile active THz devices.