Optical Switching Using Transition from Dipolar to Charge Transfer Plasmon Modes in Ge2Sb2Te5 Bridged Metallodielectric Dimers

Authors

Arash Ahmadivand, Department of Electrical and Computer Engineering, Florida International UniversityFollow
Burak Gerislioglu, Department of Electrical and Computer Engineering, Florida International UniversityFollow
Raju Sinha, Department of Electrical and Computer Engineering, Florida International UniversityFollow
Mustafa Karabiyik, Department of Electrical and Computer Engineering, Florida International UniversityFollow
Nezih Pala, Department of Electrical and Computer Engineering, Florida International UniversityFollow

Date of this Version

2-16-2017

Document Type

Article

Abstract

Capacitive coupling and direct shuttling of charges in nanoscale plasmonic components across a dielectric spacer and through a conductive junction lead to excitation of significantly different dipolar and charge transfer plasmon (CTP) resonances, respectively. Here, we demonstrate the excitation of dipolar and CTP resonant modes in metallic nanodimers bridged by phase-change material (PCM) sections, material and electrical characteristics of which can be controlled by external stimuli. Ultrafast switching (in the range of a few nanoseconds) between amorphous and crystalline phases of the PCM section (here Ge2Sb2Te5 (GST)) allows for designing a tunable plasmonic switch for optical communication applications with significant modulation depth (up to 88%). Judiciously selecting the geometrical parameters and taking advantage of the electrical properties of the amorphous phase of the GST section we adjusted the extinction peak of the dipolar mode at the telecommunication band (?~1.55??m), which is considered as the OFF state. Changing the GST phase to crystalline via optical heating allows for direct transfer of charges through the junction between nanodisks and formation of a distinct CTP peak at longer wavelengths (?~1.85??m) far from the telecommunication wavelength, which constitutes the ON state.

Originally Published In

Scientific Reports

PMID

28205643

DOI

10.1038/srep42807

Recommended Citation

Ahmadivand, Arash; Gerislioglu, Burak; Sinha, Raju; Karabiyik, Mustafa; and Pala, Nezih, "Optical Switching Using Transition from Dipolar to Charge Transfer Plasmon Modes in Ge2Sb2Te5 Bridged Metallodielectric Dimers" (2017). All Faculty. 188.
https://digitalcommons.fiu.edu/all_faculty/188

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.