间歇性兴奋剂的起源诱导铁电哈夫尼亚的强制场减小
Tianyuan Zhu1,2, Liyang Ma1, Xu Duan3
1Westlake University, Department of Physics, School of Science, Hangzhou, Zhejiang 310030, China.
Physical review letters
|February 21, 2025
概括
基于哈夫尼亚的铁电制品中的间歇性Hf(Zr) 剂显著降低了内存设备的强制场. 这种优化通过促进域壁运动来实现,从而实现更快,更低功率的切换.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 计算材料科学科学 计算材料科学
背景情况:
- 基于哈夫尼亚的铁电材料对非挥发性记忆有希望,但受到高强迫场的影响,阻碍了实际应用.
- 间位兴奋剂是一种优化铁电性能的新兴策略,特别是减少偏振切换的强制场.
研究的目的:
- 阐明使用间歇性Hf(Zr) 补充剂在Hf(Zr) O2膜中强迫场减少背后的机制.
- 确定最佳的剂策略,以提高铁电记忆器件的性能.
主要方法:
- 密度函数理论 (DFT) 计算以模拟铁电Pca21相与间歇性补充剂.
- 大规模的深潜分子动力学 (MD) 模拟以调查域壁动力学.
- 基于其大小和对切换障碍的影响,进行高通量计算以选潜在的间歇性兴奋剂.
主要成果:
- 在Pca21阶段,而不是在rhombohedral阶段,中度间歇性Hf补充剂解释了实验观察.
- 间位缺陷促进Pbcn类移动180°域壁,促进极化逆转.
- 预测处理将切换场降低到<1 MV/cm,从而实现亚纳秒切换;剂大小与切换障碍有负相关性.
结论:
- 间歇性兴奋剂,特别是具有特定的兴奋剂大小,提供了一条可行的途径,以显著减少Hf(Zr) O2铁电中的强制场.
- 了解介质缺陷在域壁运动中的作用,是设计下一代铁电内存的关键.
相关概念视频
01:31Ferromagnetism
2.4K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
2.4K
02:58Crystal Field Theory - Octahedral Complexes
26.0K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
26.0K
01:27π Electron Effects on Chemical Shift: Overview
1.0K
An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0,...
1.0K
01:26Diamagnetism
2.4K
Materials consisting of paired electrons have zero net magnetic moments. However, when these materials are placed under an external magnetic field, the moments opposite to the field are induced. Such materials are called diamagnets. Diamagnetism is the response of the diamagnets when placed in an external magnetic field.
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
2.4K
01:28Induced Electric Dipoles
4.1K
A permanent electric dipole orients itself along an external electric field. This rotation can be quantified by defining the potential energy because the external torque does work in rotating it. Then, the potential energy is minimum at the parallel configuration and maximum at the antiparallel configuration. While the former is a stable equilibrium, the latter is an unstable equilibrium.
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
4.1K
02:54Trends in Lattice Energy: Ion Size and Charge
23.6K
An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a compound is a measure of the strength of this attraction. The lattice energy (ΔHlattice) of an ionic compound is defined as the energy required to separate one mole of the solid into its component gaseous ions. For the ionic solid sodium chloride, the lattice energy is the enthalpy change of the process:
23.6K