korean english


Home > 게시판 > 세미나

양자물질초전도연구실에서 세종대학교 홍석륜 교수님을 초청하여 아래와 같이 세미나를 개최합니다.

학과 구성원 여러분의 많은 참여를 부탁 드립니다.

온라인으로 진행되는 세미나입니다.


Title: Electronic Properties of Mixed-dimensional 2D/3D Heterostructures

Speaker: 홍  석  륜  교수님 (세종대학교)

Date/time: 2021. 8. 4. (Wed.) 4:00PM

○ 온라인 참여방법: 아래의 WebEx 링크 접속


Abstract: Graphene and other 2D materials such as transition metal dichalcogenides (TMDs) and metal monochalcogenides (MMCs) have attractive physical and chemical properties. For utilization of 2D materials as electronic devices, their mixed-dimensional van der Waals (vdW) heterostructures with 3D materials are receiving much attention. To understand electronic properties of these mixed-dimensional 2D/3D heterostructures, we have performed density functional theory calculations.
We investigate the reduction of the Fermi level pinning (FLP) at Au–MoS2 interfaces by atomic passivation on Au(111). Passivating atoms prevent the direct contact between Au(111) and MoS2, and thus FLP at Au–MoS2 interfaces is reduced by weak interaction between atom-passivated Au(111) and MoS2. Especially, FLP is greatly reduced at sulfur-passivated Au-MoS2 interfaces with the smallest binding energy. Furthermore, fluorine-passivated Au(111) can form ohmic contact with MoS2, representing almost zero Schottky barrier height (SBH). We suggest that SBH can be controlled depending on the passivating atoms on Au(111).
Next, we study atomic and electronic structures of the 2D/3D heterojunction between MoS2 and Si(100) by focusing on the contact behavior dependence on the interfacial structures. Calculations show that MoS2 and clean Si(100) form an almost n-type ohmic contact with small SBH due to strong covalent bonds between them, and that the contact between MoS2 and H-Si(100) makes a p–n heterojunction with weak vdW interactions. Such a difference in contact behaviors can be explained by different electric dipole formation at the heterojunction interfaces. Similarly, 2D/3D heterostructures between GaSe and Si(111) are investigated. GaSe forms n-type contact with c-Si(111) and thus Fermi level pinning occurs at GaSe/c-Si(111) interfaces with metal-induced gap states. In the case of GaSe/H-Si(111), we identify that the interfaces form p-n heterojunction, especially with type II band alignment. Overall, it is concluded that contact properties can be varied depending on the interfacial structures of 2D/3D semiconductor heterojunctions.

번호 제목 날짜 조회 수
공지 <12/8(Thu.) 11:00am>노벨상 소개 강연 - 2016년 노벨 물리학상: 위상 응집 물리의 탄생 2016.11.28 1090351
238 <Mar.27(Wed.)> Ultrafast Movie Maker for Photo-induced Dynamics: Ultrafast Electron Microscope 2019.03.20 95497
237 <9/18> 생체계에서의 협동현상: 박테리아 수영에서부터 고분자 수송현상까지 2009.09.14 95503
236 <10/13> What has happened in the beginning of the universe? 2006.10.11 95903
235 <5/23> Nanotechnology in Korea: Present Status and Perspective 2008.05.21 95969
234 <4/3> Spin-orbit coupling induced Mott insulating state 2009.03.13 96126
233 <11/20> Particle Accelerators: Driving Forces for Energy 2009.11.16 96156
232 <4/17> Probing Stellar Explosions with Radioactive Beams* 2013.04.10 96528
231 <1/26> Hamiltonian formalism 2011.01.19 96607
230 <Sep. 30(Wed.) 4:30 PM>Local electronic structures of stacking grain boundary in bilayer graphene 2015.09.23 96627
229 <10/12> Kondo Effect in a Quantum-Dot-Topological-Superconductor Junction: A Numerical Renormalization Group Analysis 2012.10.08 96680
228 <11/4>Plasmonic Properites of Metallic Nanostructures 2009.10.30 96762
227 <6/12> Latest Results from the IceCube Neutrino Observatory 2013.06.07 96769
226 <5/14> Synthesis of Two Dimensional Materials by Chemical vapor deposition 2014.05.07 96800
225 <Oct.20(Tue) 10:00-12:00> Novel quantum transport in Weyl semimetals and double-Weyl semimetals 2015.10.23 96877
224 <12/7>유럽입자물리연구소에서의 CMS 실험 2007.12.03 96935
223 <11/27> Introduction to Terahertz and Infrared Spectroscopy 2013.11.21 96996
222 <9/8>Dynamics of one-dimensional electrons and exotic elementary excitations 2006.09.04 97036
221 <11/4 오후 3:30> Surface impurity induced self energy in bulk on a topological insulator 2013.10.23 97049
220 2016학년도 2학기 콜로퀴움 일정 2016.08.02 97082
219 <11/21> 복잡 산화물 이종접합 및 다강체 연구(Complex oxide heterostructures and multiferroics) 2012.11.15 97088