He Qiang
·Paper Publications
Indexed by: Journal paper
Journal: iSCIENCE
Included Journals: SCI
Affiliation of Author(s): 华中科技大学
Discipline: Engineering
First-Level Discipline: Electronic Science And Technology
Document Type: J
Key Words: Applied sciences; Materials science; Photonics
DOI number: 10.1016/J.ISCI.2022.104375
Abstract: All-optical switches show great potential to overcome the speed and power consumption limitations of electrical switching. Owing to its nonvolatile and superb cycle abilities, phase-change materials enabled all-optical switch (PC-AOS) is attracting much attention. However, realizing low-loss and ultrafast switching remains a challenge, because previous PC-AOS are mostly based on plasmonic metamaterials. The high thermal conductance of metallic materials disturbs the thermal accumulation for phase transition, and eventually decreases the switching speed to tens of nanoseconds. Here, we demonstrate an ultrafast switching (4.5 ps) and low-loss (2.8 dB) all-optical switch based on all-dielectric structure consisting of Ge2Sb2Te5 and photonic crystals. Its switching speed is approximately ten thousand times faster than the plasmonic one. A 5.4 dB on-off ratio at 1550 nm has been experimentally achieved. We believe that the proposed all-dielectric optical switch will accelerate the progress of ultrafast and energy-efficient photonic devices and systems.