초록

Abstract ▼

□ 연구개요
This research studied ultra-compressed plasmonic modes in graphene supported by layered structure of metal and ultra-thin dielectric spacer. Both uniform and periodic configurations were investigated. First, several plasmonic modes in graphene were studied analytically. It was discovered t

□ 연구개요
This research studied ultra-compressed plasmonic modes in graphene supported by layered structure of metal and ultra-thin dielectric spacer. Both uniform and periodic configurations were investigated. First, several plasmonic modes in graphene were studied analytically. It was discovered that acoustic graphene plasmons (AGP) is a superior platform to create ultra-compact graphene-based plasmonic devices. Then, near-fields of mid-infrared AGP were mapped for the first time, revealing unique properties of AGP propagating in a few-nm-thick dielectric. Finally, an AGP Bloch state in periodic structure was observed for the first time, proving the concept of a plasmonic crystal.

□ 연구 목표대비 연구결과
First, proposed idea of using a patterned gate electrode to create a non-uniform doping in graphene via few-nm-thin dielectric was tested. However, electrostatic doping via such a narrow dielectric turned out to be very difficult. Therefore, instead of creating periodic structure based on conventional graphene plasmons (GP), a new approach was taken: to employ AGP in a metal-dielectric-graphene structures. Graphene doping was done chemically, which provided sufficient doping level to excite mid-infrared AGP.
The near-field imaging of mid-IR AGP, demonstrated for the first time, revealed that AGP is less sensitive to ohmic loss in graphene than GP, even in a large-area CVD graphene. Therefore, it was attempted to create a plasmonic crystal based on AGP modes. Near-field measurements of AGP-based plasmonic crystal showed a dominant excitation of the plasmonic Bloch state which demonstrate a successful realization of plasmonic crystals. Summarizing, research achievements are as follows:
- create periodic structure for plasmonic dispersion control using 2D materials(graphene): 100% successful;
- demonstrate tunability of plasmonic response in periodic plasmonic structure: 100% successful (using AGP and chemically doped graphene);
- experimental demonstration of ultra-confined mid-infrared AGP with confinement factor λ_p/λ₀ > 50: 100% successful, observed λ_p/λ₀ = 56;
- demonstrate electrically tunable plasmonic crystal: on-going study, requires use of multilayer graphene for efficient doping.

□ 연구발성과의 활용 계획 및 기대효과(연구개발결과의 중요성)
Experimental discovery of ultra-confined yet low-loss AGP in large-area CVD graphene provides a new platform for the following applications:
1. strong light-matter interaction inside few-nm-scale plasmonic devices;
2. plasmonic elements for high-density photonic circuits;
3. new platform for studying non-local phenomena in metals and graphene;
4. new platform for studying strong coupling between plasmons, phonons, and vibrational states of molecules at mid-infrared frequencies.

(출처 : 연구결과 요약문 2p)

목차 Contents

• COVER ... 1
• 연구결과 요약문 ... 2
• 목차 ... 3
• 1. 연구개발과제의 개요 ... 4
• 2. 연구개발과제의 수행 과정 및 수행 내용 ... 5
• 1) Analytical and numerical study of acoustic graphene plasmons ... 5
• 2) Near-field mapping of acoustic graphene plasmons ... 7
• 3) Acoustic graphene plasmons in periodic structures ... 8
• 4) Electrostatic gating of graphene via a few-nm-thick dielectric spacer ... 11
• 3. 연구개발과제의 수행 결과 및 목표 달성 수준 ... 12
• 1) 정성적 연구개발성과(연구개발결과) ... 12
• 2) 세부 정량적 연구개발성과 ... 12
• 3) 목표 달성 수준 ... 12
• 4) 목표 미달 시 원인 분석(해당 시) ... 12
• 4. 연구개발성과의 관련 분야에 대한 기여 정도(연구개발결과의 중요성) ... 13
• 5. 연구개발성과의 관리 및 활용 계획 ... 13
• 6. 참고문헌 ... 14
• 붙임1. 세부 정량적 연구개발성과 ... 15
• 붙임2. 연구책임자 대표적 연구실적 및 증빙(요약문 및 사본) ... 18
• End of Page ... 31