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 1079490
236 <6/9(화)> 세미나 개최 안내 2015.06.09 69017
235 <9/7(금)> Kondo Effect in Chiral Orbital Bands 2012.08.31 69084
234 <5/22> Vortex partition function and 3d dualities 2012.05.21 69124
233 <8/14(Wed.)>3D-strain induced superconductivity in La2CuO4+δ using a simple vertically aligned nanocomposite approach 2019.08.13 69153
232 <March.18(Fri) 11:00> High Pressure Synthesis and Characterization of Non-Oxide Superconductors 2016.03.14 69203
231 <3/2(Fri.)11:00>Evolving magnetic interactions near a Kondo breakdown 2018.02.27 70009
230 <11/5> Optical spectroscopic probe on the surface state in three dimensional topological insulators 2012.10.24 70061
229 <8/2(Thu.) 2:00pm>Status of multifractional theories 2018.07.24 70340
228 <7/15(Fri.) 14:00> Electronic quasiparticles in the quantum dimer model 2016.07.12 70398
227 <9/14> High temperature superconductivity and fluctuating stripe 2012.09.10 70618
226 <11/22> Spin polarization of photoelectrons from a topological insulator 2012.10.22 70874
225 <2/9(월) 오전 11시> 특별 초청세미나 개최 안내 file 2015.02.03 71052
224 <12/30> Correlation between Raman scattering and conductance in a molecular junction 2013.12.23 71103
223 <10/5> Gauge fields. Past, present, future. 2012.10.05 71271
222 <10/24> Dung-hai Lee 교수와의 간담회 2012.10.23 71284
221 <9/7> On Dark Matter and its indirect detection with box-shaped gamma-rays 2012.09.05 71531
220 <March 8(Tue) 18:00> Unsolved puzzles of Gamma-Ray Bursts 2016.03.03 71660
219 <10/11(Tue.) 15:00>Analysis of Individual Terrestrial Gamma-ray Flashes 2016.10.10 71874
218 <6/15(Fri.) ~ 16(Sat.)> Formation of first star and galaxy, Gravitational waves from Binary Mergers of Sub-Solar Mass Dark Black Holes 2018.06.12 72461
217 <12/2(화)> Emergent Quantum Phenomena in SrTiO3 Heterostructures 2014.11.21 72732