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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Charge-Gradient-Induced Ferroelectricity with Robust Polarization Reversal.
Shipu Xu1, Xing Xu1, Shidang Xu2
1Songshan Lake Materials Laboratory, Dongguan523808, China.
Nano Letters
|December 21, 2022
Summary
Researchers developed a novel ferroelectric material exhibiting robust polarization reversal for errorless data storage. This charge-gradient-induced ferroelectricity enables first-order phase transitions, overcoming limitations of traditional ferroelectric devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Ferroelectric tunnel junctions (FTJs) are crucial for advanced data storage but face challenges due to second-order phase transitions causing intermediate states.
- Robust polarization reversal is essential for reliable and errorless data storage applications.
Purpose of the Study:
- To propose and demonstrate a novel charge-gradient-induced ferroelectricity.
- To achieve robust polarization reversal via a first-order phase transition in a ferroelectric material.
- To fabricate and characterize FTJs based on this new ferroelectric material.
Main Methods:
- Pulsed laser deposition was used to modulate stoichiometric oxygen in Bi2O2Se/Bi2Se3O9 bilayers.
- Ferroelectric hysteresis loops were measured to analyze polarization reversal at room temperature.
- Scanning capacitance microscopy and current-voltage measurements were employed to characterize FTJ performance.
Main Results:
- A charge-gradient-induced polarization exhibiting out-of-plane polarity and abrupt reversal was achieved.
- The material demonstrated a stable coercive field with minimal increase after 300 reversals.
- Fabricated FTJs showed an electroresistance of 100 with reliable ON/OFF switching and 360s retention.
Conclusions:
- Charge-gradient-induced ferroelectricity offers a promising pathway for robust polarization reversal.
- The demonstrated FTJs exhibit potential for high-performance, errorless data storage.
- The ON/OFF switching mechanism involves a combination of tunneling and thermionic emission.
Keywords:
Ferroelectric tunnel junctionasymmetric junction barrierelectroresistanceextrinsic ferroelectricityMore Related Videos
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