Ma Zhijun, Zhang Qi, Tao Lingling, Wang Yihao, Sando Daniel, Zhou Jinling, Guo Yizhong, Lord Michael, Zhou Peng, Ruan Yongqi, Wang Zhiwei, Hamilton Alex, Gruverman Alexei, Tsymbal Evgeny Y, Zhang Tianjin, Valanoor Nagarajan
Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan, 430062, P. R. China.
School of Materials Science and Engineering, University of New South Wales, Sydney, 2052, Australia.
Adv Mater. 2022 Sep;34(35):e2205359. doi: 10.1002/adma.202205359. Epub 2022 Aug 2.
Resonant tunneling is a quantum-mechanical effect in which electron transport is controlled by the discrete energy levels within a quantum-well (QW) structure. A ferroelectric resonant tunneling diode (RTD) exploits the switchable electric polarization state of the QW barrier to tune the device resistance. Here, the discovery of robust room-temperature ferroelectric-modulated resonant tunneling and negative differential resistance (NDR) behaviors in all-perovskite-oxide BaTiO /SrRuO /BaTiO QW structures is reported. The resonant current amplitude and voltage are tunable by the switchable polarization of the BaTiO ferroelectric with the NDR ratio modulated by ≈3 orders of magnitude and an OFF/ON resistance ratio exceeding a factor of 2 × 10 . The observed NDR effect is explained an energy bandgap between Ru-t and Ru-e orbitals driven by electron-electron correlations, as follows from density functional theory calculations. This study paves the way for ferroelectric-based quantum-tunneling devices in future oxide electronics.
共振隧穿是一种量子力学效应，其中电子输运由量子阱（QW）结构内的离散能级控制。铁电共振隧穿二极管（RTD）利用量子阱势垒的可切换电极化状态来调节器件电阻。在此，报道了在全钙钛矿氧化物BaTiO₃/SrRuO₃/BaTiO₃量子阱结构中发现的稳健的室温铁电调制共振隧穿和负微分电阻（NDR）行为。共振电流幅度和电压可通过BaTiO₃铁电体的可切换极化进行调节，NDR比率调制约3个数量级，开/关电阻比超过2×10⁶倍。根据密度泛函理论计算，观察到的NDR效应可解释为电子 - 电子相关性驱动的Ru-t和Ru-e轨道之间的能带隙。该研究为未来氧化物电子学中基于铁电的量子隧穿器件铺平了道路。
