logo

korean english

게시판

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

https://skku-ict.webex.com/meet/tp8701


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 1090361
338 <9/13> Multiferroic properties of BiFeO3 single crystal and 1D-Chain system 2007.09.04 83249
337 <6/10> 초전도 분야 특별세미나 개최 file 2011.06.01 83221
336 2006학년도 2학기 콜로퀴움 일정 2006.10.23 83218
335 <1/22>Vortices, Q-balls, domain walls on dielectric M2 brane 2009.01.19 83128
334 <11/3>고온 초전도와 MgB2 초전도체-미래전망 2006.11.03 83017
333 <9/7> Magnets and Science at the NHMFL 2011.09.06 82840
332 <5/8> A brief introduction to holographic entanglement entropy 2012.05.07 82829
331 <11/3> Special Seminar - "2011 Nobel Physics: The beginning and the end of the universe" 2011.10.27 82811
330 Square lattice S=1/2 Heisenberg spin systems: Vanadium oxides and phosphates 2006.01.12 82673
329 <Nov. 30(Wed.) 4:30 PM> Chiral solitons for topological informatics 2016.11.23 82663
328 <11/9> 자기저항 현상과 스핀트로닉스, 그리고 금속성 산화물 자성체 2007.11.05 82395
327 <8/1(Wed.) 4:00pm>Band Topology in Nodal Line Semimetals with Z2 Monopole Charges 2018.07.23 82226
326 <5/9> Gravity dual of (Non-)Fermi Liquids from Entanglement Entropy 2012.05.07 82161
325 <11/19(수)> 3D topological insulators with magnetic impurities 2014.11.13 82126
324 <3/11(Mon) 10:30 am ~ >Probing Dark Matter at LIGO and Beyond 2019.03.04 82081
323 콜로퀴움입니다. 2005.12.29 82025
322 <9/17>Computational studies of materials and nanostructures 2010.09.08 81898
321 <8/19(Mon) 14:00 ~ >Exploring topological matter in an atomic quantum simulator file 2019.07.26 81870
320 <10/12> Introduction to the Proton Engineering Frontier Project 2011.10.10 81817
319 <4/27> BPS Vortices in Non-relativistic M2-brane Chern-Simons-matter Theory 2009.04.21 81815