visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-05-25 14:00 
일시 May. 25th (Wed), 14:00 
장소 E6 Room(#2501) 
연사 Dr. Duk-Hyun Choe(Samsung Advanced Institute of Technology) 

Physics Seminar

 

 

 

Atomic-level insights into ferroelectric switching and preferred orientation of ultrathin hafnia

 

Duk-Hyun Choe

Samsung Advanced Institute of Technology

May. 25th (Wed), 14:00, E6 Room(#2501)

 

Over the past decade there has been a resurgence of interest in ferroelectric (FE) devices in the semiconductor device community. This interest was sparked by the discovery of ferroelectricity in a simple binary oxide, hafnia. Unlike conventional FE perovskite, FE hafnia exhibits ultra-scalable ferroelectricity compatible with Si electronics, providing an unprecedented opportunity for the use of FEs in advanced memory and logic devices. Many proof-of-concept devices based on FE hafnia are indeed showing some promise. However, their practical engineering is still largely relying on trial-and-error process that lacks a clear theoretical guidance, and it remains challenging to rationally design the FE devices for targeted applications. Thus, the community is now calling for more fundamental investigations on the physics of ferroelectricity in hafnia.

In this presentation, we briefly review the status of the field and provide our new understanding on FE switching and surface stability of hafnia. We will first introduce an ultralow FE switching mechanism that can enable rapid growth of the FE domains in hafnia [1]. We also establish a new class of topological domain walls in HfO2, which can help understand complex domain structures often present in FE hafnia samples. Next, we present our systematic study of surface-functionalized FE hafnia [2]. We show that their remnant polarization (Pr) and coercive field (Ec) can strongly depend on the surface treatments, providing a possible explanation for the enhancement of Pr in ultrathin hafnia with preferred orientation [3,4]. We believe our study represents an important step towards bridging the gap between practical engineering and the first-principles simulations in the field of FE hafnia.

 

[1] D.-H. Choe et al., Mater. Today 50, 8 (2021).

[2] D.-H. Choe et al., IEDM (2021).

[3] S. S. Cheema et. al., Nature 580, 478 (2020)

[4] H. Lee, D.-H. Choe, S. Jo 36499 (2021).13,  ACS Appl. Mater. Interfaces et. al.,

 

Contact: Prof. Chan-Ho Yang (chyang@kaist.ac.kr) ,

Departmentof Physics / Center for Lattice Defectronics

 

Department of Physics, KAIST

번호 날짜 장소 제목
공지 2022-10-24 16:00  E6 #1501(공동강의실)  Physics Colloquim(Fall 2022)
공지 2022-09-21 10:30  E6-1 #1501  [Update 세미나 영상] Distinguished Lecture 'The Magic of Moiré Quantum Matter' Prof. Pablo Jarillo-Herrero(Department of Physics, MIT)
공지 2022-10-28 11:00  E6-2 #1323  [Update 세미나영상] (응집물리 세미나) Machine-Learning-Guided Prediction models and Materials discovery for high Tc cuprates
공지 2022-10-07 11:00  E6-2 #1323  [Update 세미나 영상] (응집물리 세미나) Competing orders in a vanadium-based kagome metal monolayer
공지 2022-09-23 11:00  E6-2 #1323  [Update 세미나 영상] (응집물리 세미나) Steady Floquet-Andreev states in graphene Josephson junctions
공지 2022-09-22 11:00  E6-1 #1323  2022 가을학기 응집물리 및 광학 세미나 전체 일정
196 2022-01-18 14:00  KI bldg. 5th fl. Room B501 & Zoom  Data-driven interrogation of biological dynamics: from subcellular interactions to neuronal networks in vivo file
195 2022-01-17 14:00  E6-2 Room 2502  Five Lectures on Observational Probes of Dark Energy file
194 2022-01-11 15:00  E6 #1501  Ultrafast optical studies on CDW collective modes of the Weyl-CDW (TaSe4)2I file
193 2022-01-12 11:00  Zoom and E6 #1323  Spectroscopic study of trapped ions towards probing dark matter and new physics file
192 2019-02-21 16:00  #5313, E6-2  B-meson charged current anomalies - Theoretical status file
191 2020-02-20 16:00  #1323, E6-2  Unconventional superconductivity in the locally non-centrosymmetric heavy-fermion CeRh2As2 file
190 2020-02-13 16:30  E6-6, #119  Enhanced Light-Matter Interactions in Graphene with Noble Metal Plasmonic Structures file
189 2020-02-12 13:00  E6-2, #5318  From inflation to new weak-scale file
188 2021-02-17 09:00  Online  석학 대중 강연 및 강의 시리즈 file
187 2021-02-15 17:00  Zoom  Magnetic Cluster Octupole Domain evolutation in chiral antiferromagnets file
186 2019-02-25 16:00  Rm. 1501 (E6)  Spring 2019: Physics Colloquium file
185 2021-02-02 14:30  Zoom  Quantum- & Nano-Photonics 세미나(Integrated Nanophotonics with Metamaterials, Microcomb, and Atomic Systems) file
184 2018-02-12 15:00  #C303, (Creation Hall 3F, KAIST Munji Campus)  The recent result of XMASS Experiment
183 2017-02-01 14:00  #1323(E6-2. 1st fl.)  Quantum electron optics using flying electrons
182 2019-12-05 16:00  #1323, E6-2  Subwavelenth Photonic Devices: From Single Photon Sources to Solar Cell file
181 2019-12-03 16:00  #1323, E6-2  Toward Quantum Materials with Correlated Oxides file
180 2019-12-27 15:00  E6-2,#5318  The superconducting order parameter puzzle of Sr2RuO4 file
179 2020-12-02 10:00  Zoom  Recent progress in Axion Dark Matter eXperiment (ADMX) technology file
178 2019-12-18 16:00  #1323, E6-2  Road to Higher Tc Superconductivity file
177 2019-12-13 13:30  #1323, E6-2  Biophysics Mini-symposium at KAIST file