题目：超高质量二维异质界面诱导的新奇量子物态
报告人：王雷教授（南京大学）
时间：2021年11月26日下午3:30-5:00
地点：田家炳楼203平星报告厅
Abstract: Developing new methods to synthesize new materials is important for condensed matter physics. With the development of nanotechnology, constructing new material structures using nanoscale building blocks as small as a molecule or atom becomes possible. Precisely controlling the composition and structure of these nanoscale building blocks brings us materials with completely new electronic, mechanical, optical properties. Two-dimensional (2D) material is one of the important platforms for these novel systems. Although 2D materials such as graphene or TMDs are promised to carry remarkable electronic performance, the experimental reality is that they are highly sensitive to disorder from the environment. I will present the techniques I developed to controllably assemble 2D materials layer by layer with ultraclean interfaces[1]. In addition, these new techniques allow us to ‘mix and match’ different 2D materials together layer by layer to form heterostructures, with controlling their positions, thickness and lattice twist angles to achieve new material properties. I will talk about how to tune these nobs to achieve the bandstructure engineering [2] at the interfaces between the different atomic planes and the new physics [3] revealed by these structures. I will conclude my talk with our recent results on twisted bilayer TMDs as a model system to study interaction-driven phenomena in flat bands with dynamically tunable interactions[4].
[1] L. Wang et al, Science, 614-617 (2013).
[2] L. Wang et al, Science 350, 1231-1234 (2015).
[3] L. Wang*, et al, Nature Materials 19, 861-866 (2020)
[4] A. Ghiotto…L. Wang* et al, Nature 597, 345-349, (2021).
王雷， 2005年在新加坡国立大学获得电子工程系本科学位，2008年获得新加坡国立大学电子工程系硕士学位， 2014年获得美国哥伦比亚大学电子工程系博士学位。2014-2015年美国哥伦比亚大学纳米创新中心博士后，2015-2019年美国康奈尔大学Kavli纳米科学研究所任研究员，2019年加入南京大学，任南京大学7163银河官方网址和固体微结构国家重点实验室教授，博士生导师。王雷教授在一流期刊发表文章40余篇，被引用19000余次，包括第一/通讯作者论文包括Science (4篇)、Nature(2篇)、Nature Materilas(1篇)、Nature Photonics(1篇) 等。其2013年发表在Science期刊的科研成果，发明了二维材料的Pick-up转移和堆积技术，突破性地提高了二维材料的电子器件质量，并在实验上推进了二维材料异质结构研究方向的发展，在此领域上取得了多个重要的科研成果，包括实验观测到霍夫施塔特蝴蝶能谱、可调控的分数量子霍尔态、量子分形体系中的分数量子霍尔态、基于单层原子的可调控压电效应、超快表面等离激元和可调控激子，转角二维半导体中的相关绝缘态。王雷教授目前的主要研究方向为二维材料多层异质结器件微加工及其电、磁输运性质，电子关联体系等。