Graphene Based Surface Plasmon Polariton Modulator Controlled by Ferroelectric Domains in Lithium Niobate.

Hao Wang,Hang Su,Jingwen Zhang,Siren Li,Hua Zhao,Guangwei Hu

doi:10.1038/srep18258

Abstract

We proposed a ferroelectric domain controlled graphene based surface plasmon polariton modulator. Ferroelectricity-induced electronic and optical property tuning of graphene by domain in lithium niobate was theoretically investigated considering both interband and intraband contributions of surface conductivity. With the corrected Sellmeier equation of lithium niobate, the propagation of transverse magnetic mode surface plasmon polaritons in an air/graphene/lithium niobate structure was studied when monolayer graphene was tuned by down polarization direction ferroelectric domain with different polarization levels. The length of the ferroelectric domain was optimized to be 90 nm for a wavelength of 5.0 μm with signal extinction per unit 14.7 dB/μm, modulation depth 474.1 dB/μm and figure of merit 32.5. This work may promote the study of highly efficient modulators and other ultra-compact nonvolatile electronic and photonic devices in which two-dimensional materials and ferroelectric materials are combined.

Highlights

-2 intrinsic n-doped p-doped transitions from the visible range to mid-wave infrared (MWIR) range
Motivated by the recent developments in nanometer-scale ferroelectric domain growth technology and the future in data storage, information processing, and photonic devices[21,22,23,24,25], we theoretically investigated the graphene surface plasmon polariton (SPP) modulator controlled by ferroelectric domains in congruent grown lithium niobate (CLN)
With random-phase approximation (RPA) under the self-consistent-field linear response theory, the surface conductivity of graphene can be derived from the Kubo formula consisting of both interband and intraband transitions[1] as follows: σS (ω) =

Summary

Introduction

-2 intrinsic n-doped p-doped transitions from the visible range to mid-wave infrared (MWIR) range. The SPP wave propagating distance and lateral penetration length were studied with different chemical potentials and wavelengths. The length of the ferroelectric domain was optimized to be 90 nm for wavelength at 5.0 μ m considering the signal extinction, modulation depth and power ratio. The combination of lithium niobate (LN, renowned as “optical silicon”) with 2D materials may lead to new nonvolatile integration devices, plasmonic modulators, and other ultra-compact electronic and photonic devices

Methods

Results

Conclusion