2018/09/25(Tue) 10:30 -12:00 五樓第一會議室 5F, 1st Meeting Room
Title
Two-dimensional ferroelectric tunnel junction
Speaker
段純剛教授 (華東師範大學極化材料與器材教育部實驗室) Prof. Chun-Gang Duan (Key Laboratory of Polar Materials and Devices, Ministry of Education, East China Normal University)Abstract
Ferroelectric tunnel junctions (FTJs) have triggered considerable attention in the advanced applications of non-volatile information devices. However, critical thickness for ferroelectricity limits FTJs towards their application at the nanoscale. Recently, ferroelectricity is demonstrated to intrinsically exist in some two-dimensional (2D) materials. Here, through the opposite dopant on the two sides of the monolayer group-IV monochalcogenides (GIVMs), we design a novel 2D-FTJ employing p-type semiconductor/ferroelectric/n-type semiconductor homostructure, coupling the electron tunneling with the in-plane ferroelectricity. This structure makes it possible to dynamically modulate tunneling barrier height as well as the width in response to the ferroelectric polarization reversal, and promises to realize a significantly enhanced tunneling electroresistance (TER) effect. Combining first-principles calculations with non-equilibrium Green’s function formalism, herein, we reveal this mechanism by using In:SnSe/SnSe/Sb:SnSe homostructure as a prototypical example, where a large TER effect of around 1.46×103 % is obtained. Compared with the normal vertical FTJs, this lateral 2D-FTJ enormously improves the TER effect and show exciting prospects for device application with higher data integration and reliable information retention in the future.
Language
演講語言 (Language): in English