ABSTRACT

Polarisation vortex structures in ferroelectric materials are being considered as a promising alternative to current memory cells due to the merit of high storage density. However, ferroelectric storage devices would inevitably be affected by external loads. When an applied mechanical or electrical load reaches its critical value, it could cause the loss of stored data because the polarisation vortex loses the stability. Some phase field simulations were conducted to investigate the stability of the polarisation vortex under different stresses or curled electric fields. The results show that the polarisation vortex structure has the strongest resistance to a tensile stress, followed by a compressive stress, but the weakest to a curled electric field. The temperature sensitivity of the polarisation vortex structure to resist different loads is also significantly different. The temperature sensitivity is the strongest for the curled electric field, followed by for the tensile stress, but the weakest for the compressive stress. This work would be helpful for tuning polarisation vortex and designing ferroelectric storage devices in specific working environments.

摘要

由于高存储密度的优点，铁电材料中的极化涡旋结构被认为是当前存储单元的有前途的替代品。然而，铁电存储设备不可避免地会受到外部负载的影响。当施加的机械或电气负载达到其临界值时，可能会导致存储数据丢失，因为极化涡流失去稳定性。进行了一些相场模拟以研究极化涡旋在不同应力或卷曲电场下的稳定性。结果表明，极化涡旋结构对拉应力的抵抗力最强，其次是压应力，但对卷曲电场的抵抗力最弱。极化涡流结构抵抗不同载荷的温度敏感性也有显着差异。卷曲电场的温度敏感性最强，其次是拉应力，但最弱的是压应力。这项工作将有助于在特定工作环境中调整极化涡旋和设计铁电存储设备。