Thermodynamic criterion for searching high mobility two-dimensional electron gas at KTaO3 interface

• 作者: Wen-Xiao Shi Hui Zhang Shao-Jin Qi Jin-E Zhang Hai-Lin Huang Bao-Gen Shen Yuan-Sha Chen Ji-Rong Sun
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（7）
• 所属期刊栏目: RAPID COMMUNICATION
• 页码范围: 80-84
• 页数: 5页
• 语种: 英文
• DOI: 10.1088/1674-1056/ac078c

摘要

Two-dimensional electron gases (2DEGs) formed at the interface between two oxide insulators present a promising platform for the exploration of emergent phenomena.While most of the previous works focused on SrTiO3-based 2DEGs,here we took the amorphous-ABO3/KTaO3 system as the research object to study the relationship between the interface conductivity and the redox property of B-site metal in the amorphous film.The criterion of oxide-oxide interface redox reactions for the B-site metals,Zr,A1,Ti,Ta,and Nb in conductive interfaces was revealed:the formation heat of metal oxide,△H0f,is lower than-350 kJ/(mol O) and the work function of the metal Φ is in the range of 3.75 eV＜ Φ ＜ 4.4 eV.Furthermore,we found that the smaller absolute value of △H0f and the larger value of Φ of the B-site metal would result in higher mobility of the two-dimensional electron gas that formed at the corresponding amorphous-ABO3/KTaO3 interface.This finding paves the way for the design of high-mobility all-oxide electronic devices.