Abstract-Controlling the terahertz radiation with subwavelength blocky patterned CoFeB/Pt heterostructures

Bangju Song, Yuna Song, Shunnong Zhang, KaiLong Jin, Weihua Zhu, Qin Li, Zongzhi Zhang, Xian Lin, Ye Dai, Xiaona Yan,

https://iopscience.iop.org/article/10.7567/1882-0786/ab4d2b/pdf

We report the broadband emission of THz pulse in the metallic patterned ferromagnetic heterostructures CoFeB/Pt based on inverse spin-Hall effect, by illuminating a train of linearly polarized 120 fs-wide laser pulses at 800 nm. The spatial-temporal distribution of charge currents by changing the length of the subwavelength rectangular metal-blocks allows not only effectively controlling the magnitude, but also subtly tuning the center frequency and bandwidth of the emitted THz pulses. Our results will open new avenues for the study of modulated spintronic-based THz emitters.

Abstract-Terahertz time-domain spectroscopy for magnonics and magnetotransport

Zuanming Jin, Xiumei Liu, Shunnong Zhang, Wanying Zhao, Xian Lin, Zongzhi Zhang, Chao Jin, Shixun Cao, Zhenxiang Cheng, Guohong Ma, Jianquan Yao,

https://www.osapublishing.org/abstract.cfm?uri=ISUPTW-2018-ThD2

Terahertz (THz) time-domain spectroscopy can be used to investigate the spintronic effects, such as low-energy magnons and magnetotransports, in the ultrafast operation regime, sub-picosecond time scale and/or terahertz frequency range.

© 2018 OSA

Abstract-Photoinduced terahertz radiation and negative conductivity dynamics in Heusler alloy Co2MnSn film

Shunnong Zhang, Zuanming Jin, Xiumei Liu, Wanying Zhao, Xian Lin, Chao Jing, and Guohong Ma

https://www.osapublishing.org/ol/abstract.cfm?uri=ol-42-16-3080&origin=search

We report the broadband terahertz (THz) radiation in ferromagnetic half-metallic Heusler alloy Co2MnSn${\mathrm{Co}}_2\mathrm{MnSn}$ thin film upon the irradiation of a femtosecond laser pulse at room temperature. The magnetic-, sample symmetry-, and pump fluence-dependent THz emission reveals that the THz radiation is originated from the magnetic-dipole radiation, i.e., the light-induced subpicosecond demagnetization. In addition, by optical pump-THz probe spectroscopy, we found that the photoexcited increase of the scattering rate of hot carriers thereby leads to the photoinduced negative THz conductivity in Co2MnSn${\mathrm{Co}}_2\mathrm{MnSn}$ thin film.

© 2017 Optical Society of America