Terahertz multi-level nonvolatile optically rewritable encryption memory based on chalcogenide phase-change materials

Directional terahertz holography with thermally active Janus metasurface

“…In that case, the information capacity and application scenarios will increase dramatically. Moreover, the reconfigurable Janus metasurface may be realized by other tunable materials, such as liquid crystal 34 , 51 , 52 , germanium antimony telluride (GST) 53 – 55 or hydrogenated/dehydrogenated magnesium 32 , 56 . A similar reconfigurable direction-dependent metasurface can be developed based on the proposed scheme and fulfill multiple functionalities in other frequency bands.…”

Machine learning enabled rational design for dynamic thermal emitters with phase change materials

“…Second, as for a dynamic device, the VO 2 -based thermal emitter undergoes a time-dependent phase-transition process and has transient intermediate states between the initial and final steady states; however, the transient intermediate states are not considered in the manuscript for simplification. Moreover, not limited to VO 2 , other phase-change materials such as Ge-Sb-Te (GST) and Ge-Sb-Se-Te (GSST) can also be considered as another degree of freedom in the design 49 , 50 , 51 and the experimental realization is desired in the future.…”

Recent Advances in Terahertz Manipulations Using C‐Shape‐Split‐Ring‐Resonator Metasurfaces (Review)

“…Strategies for achieving tunability that have been explored mostly include optical pumping, [116][117][118][119][120][121][122][123] electrical control, [124][125][126][127][128][129][130][131][132][133][134][135] and thermal control. [136][137][138][139][140][141][142] Next, we will briefly present recent progress in the active control of THz waves based on CSRR metasurfaces. One of the most common approaches to achieve active control is through modulation of the free carrier density in materials by means of optical pumping or electrical gating.…”

“…GST has been employed to create a range of functional devices, such as dynamic beam splitters, bifocal metalenses, dual-mode focusing optical vortex generators, holography, and switchable meta-lenses. [138][139][140][141][142] Zhou et al introduced two types of CSRR metasurface devices based on whole GST films in order to accomplish temperature-controlled holography and simultaneous phase and interference encryption. [138] Metasurfaces based on GST can encrypt information in one switched state and store concealed information in another state by applying external thermal stimuli across the entire metasurface.…”