报告人：Yoshihiro Iwasa（日本东京大学教授）

主持人：王健 开云app体育 物理学院教授 

时间：2023年5月26日（星期五）15:00—16:00

地点：物理学院思源多功能厅（西301）

报告摘要:

Condensed matter, due to its large number of atoms, exhibits a variety of unexpected quantum phases, including superconductivity, magnetism, correlated insulators, and ferroelectrics, and topological phases. In this lecture, I will give a brief review on the electric field (and more broadly voltage) control of quantum matter, with particular interest in two-dimensional van der Waals materials.

Using the device structure, called field effect transistor (FET), we are able to control the carrier density by application of the gate voltage. Since the carrier density is the key parameter for determining the electronic properties of solids, the voltage can be a knob of tuning the electronics state in principle. We have developed a new transistor by replacing the gate insulator with the ionic conductor (and electrical insulator) more than a decade ago. With this device, we found that the accumulated carrier density is one to two orders of magnitude enhanced, and using this device, we first discovered electric field induced superconductivity in an insulator [1]. We called this device electric double layer transistor (EDLT), and have shown that this device is powerful in electric field control of quantum phases in superconductors [2], Mott insulators [3], and ferromagnets [4].

This electrochemical device enables us to further expand the performance of gating devices [5]. One is the layer-by-layer etching to form the monolayer materials [6]. The other is the intercalation of ions into materials [7]. These extensions further push forward the capability of transistor devices for controlling the quantum phases of matter.

References

[1] K. Ueno et al., Nat. Mater. 7, 855 (2008).

[2] Y. Saito, T. Nojima and Y. Iwasa, Nat. Rev. Mater. 2, 16094 (2017). .

[3] M. Nakano et al., Nature 487, 459 (2012).

[4] Y. Yamada et al., Science 332, 1065 (2011).

[5] S. Z. Bisri et al, Adv. Mater. 29, 1607054 (2017).

[6] J. Shiogai et al., Nat Phys. 12, 42 (2016).

[7] Y. Nakagawa et al., Science 372, 190 (2021)

报告人简介：

Yoshihiro Iwasa

Professor

Quantum Phase Electronics Center and Department of Applied Physics

The University of Tokyo

Team Leader

RIKEN Center for Emergent Matter Science

Email: iwasa@ap.t.u-tokyo.ac.jp

Education

PhD in Applied Physics, University of Tokyo, Japan, 1986

Professional Activities

Team Leader, RIKEN, 2012-

Professor, University of Tokyo, 2010-

Professor, Tohoku University, 2001

Associate Professor, Japan Advanced Institute for Science and Technology, 1994

Award and Honors

Nishina Memorial Prize, 2019

Honda Frontier Prize, 2015

The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology, 2014

Japan IBM Science Prize, 2004

Research Interests

2D Materials

2D Superconductivity

Ionic gating and Iontronics

现场参会报名：请于5月25日24:00前提交报名信息。

直播：扫描下方二维码观看

开云app体育 物理学院学术论坛创办于2020年9月，邀请国内外高校和研究机构高层次科技创新领军学者就物理学及相关领域的基础前沿探索、关键技术突破和热点问题等作学术演讲，旨在推进高质量学术交流，促进学科交叉融合和开拓新兴特色方向研究，培养具有科学精神、全球视野、创新能力、批判性思维的优秀青年人才。

主办：开云app体育 物理学院

联系人：孙嘉琪 jqsun@pku.edu.cn