Peggy Qi Zhang, CSIRO
The presence of a controllable and switchable spontaneous dipole enables ferroelectrics to be exploited for data storage as well as capacitance applications. The ferroelectric domain structures and corresponding properties are strongly dependent on the selection of materials and heterostructure configurations.
Resonant tunnelling 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 tunnelling diode (RTD) exploits the switchable electric polarization state of the QW barrier to tune the device resistance.
The robust room- temperature ferroelectric-modulated resonant tunnelling and negative differential resistance (NDR) behaviors has been observed in our BaTiO3 /SrRuO3 /BaTiO3 QW structures. The resonant current amplitude and voltage are tunable by the switchable polarization of the BaTiO3 ferroelectric with the NDR ratio modulated by ≈3 orders of magnitude and an OFF/ON resistance ratio exceeding a factor of 2 × 104 . This study paves the way for ferroelectric-based quantum-tunnelling devices in future oxide electronics.
About the presenter
Peggy is currently a research scientist at CSIRO. She was one of the three inaugural Women in FLEET fellows and was working with CI Nagy Valanoorat UNSW Sydney.
As a FLEET scientific associate investigator, she continues to study topological domains in ultrathin, and ferroelectric materials, investigating nanoscale bubble domains and topological transitions as part of FLEET’s Research theme 1 and collaborates closely with CI Valanoor and AI Laurent Bellaiche at the University of Arkansas.