Abstract:

　　Ferromagnets and ferroelectrics are “ferroic” materials that exhibit spontaneous order of magnetic and electric dipoles below a critical temperature, respectively. The elementary quasiparticle excitations of magnetic materials are known as spin waves or their quanta “magnons”, which have been extensively studied in the field of spintronics as the carriers of spin currents. However, it has been an entirely open question whether an analogous quasi-particle exists in ferroelectric materials - an important material class with many technological applications. In this talk, I positively answer this fundamental question by proposing a new class of quasi-particles “ferrons” in ferroelectrics that carry energy as well as an electric dipole [1,2] and address the associated electric polarization transport [3]. Based on the ferron spectrum, we predict temperature-dependent pyroelectric and electrocaloric properties, electric-field-tunable heat transport that has been confirmed by the experiment [4], ferron-photon hybridization, and non-local ferron drag thermoelectric effect in ferroelectric van der Waals heterostructure [5].

References

[1]   P. Tang et al., Phys. Rev. B 106, L081105 (2022).

[2]   P. Tang et al., Phys. Rev. B 109, L060301 (2024).

[3]   P. Tang, et al., Phys. Rev. Lett. 128, 047601(2022).

[4]   B. L Wooten et al., Science Advance 9 eadd7194 (2023).

[5]   P. Tang et al. Phys. Rev. B 107, L121406 (2023)

报告人简介：

　　唐萍， 2020年博士毕业于中国科学院物理研究所韩秀峰老师课题组； 2017年-2019年，在美国亚利桑那大学张曙丰教授课题组进行联合博士研究；2021年4月至今，任日本东北大学助理教授；从事凝聚态理论物理研究，主要关注铁电和磁性材料中的准粒子集体激发的性质，提出了铁电材料中“ferron”准粒子激发以及相关的电极化输运的概念，在Phys. Rev. Lett和 Phys. Rev. B等期刊发表论文30余篇。