报告题目：Magnon-polaron transport in magnetic insulators

报告人：沈卡  教授（北京师范大学）

报告时间：2019年7月29日（周一）11:00

报告地点：物理楼313报告厅

报告人简介：沈卡，北京师范大学物理学系教授。2012年获得中国科学技术大学博士学位；2012-2014年美国密苏里大学哥伦比亚分校博士后；2014-2017年荷兰代尔夫特理工大学博士后；2017年北京师范大学物理学系教授。

报告摘要： We theoretically investigate the transport properties of magnon polaron, the hybridization states of the magnon and phonon in the presence of magnetoelastic coupling in magnetic insulators. We will first discuss the coherent dynamics of magnon polaron generated by a focused ultrafast laser pulse[1,2], which shows different propagating characteristics due to thermal (laser heating) and non-thermal (magneto-optical) effects. In the second part, we will discuss the incoherent magnon-polaron transport in spin Seebeck configuration [3,4,5]. We will analyze the origin of the anomaly in the magnetic field dependence of spin Seebeck coefficient observed in experiment. A temperature-driven anomaly is also predicted in GdIG, based on the calculation of finite temperature magnon spectrum[6].

References:

[1] Shen and Bauer, PRL 115, 197201 (2015); JPD 51, 224008 (2018)

[2] Hashimoto, KS, et al., Nature Commnun. 8, 15859 (2017)

[3] Kikkawa, KS, et al., PRL 117, 207203 (2016)

[4] Flebus, KS, et al., PRB 95, 144420 (2017)

[5] Shen, PRB 99, 024417 (2019)

[6] Shen, NJP 20, 043025 (2018)