Journal
ACS APPLIED MATERIALS & INTERFACES
Volume 13, Issue 17, Pages 20875-20884Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acsami.1c03776
Keywords
thin-film heterostructures; spin pumping; interfacial spin transparency; spin-mixing conductance; time-resolved magneto-optical Kerr effect; Gilbert damping parameter
Funding
- S. N. Bose National Centre for Basic Sciences (SNBNCBS), India [SNB/AB/18-19/211]
- SNBNCBS
- UGC, Govt of India
Ask authors/readers for more resources
Pure spin current generated by spin pumping mechanism, with high efficiency and transparency, is crucial for future spin-orbitronic devices. The giant interfacial spin transparency and its strong dependence on crystal structures of W can contribute significantly to the development of such devices.
Pure spin current has transformed the research field of conventional spintronics due to its various advantages, including energy efficiency. An efficient mechanism for generation of pure spin current is spin pumping, and high effective spin-mixing conductance (G(eff)) and interfacial spin transparency (T) are essential for its higher efficiency. By employing the time-resolved magneto-optical Kerr effect technique, we report here a giant value of T in substrate/W (t)/Co20Fe60B20 (d)/SiO2(2 nm) thin-film heterostructures in the beta-tungsten (beta-W) phase. We extract the spin diffusion length of W and spin-mixing conductance of the W/CoFeB interface from the variation of damping as a function of W and CoFeB thickness. This leads to a value of T = 0.81 +/- 0.03 for the beta-W/CoFeB interface. A stark variation of Geff and T with the thickness of the W layer is obtained in accordance with the structural phase transition and resistivity variation of W with its thickness. Effects such as spin memory loss and two-magnon scattering are found to have minor contributions to damping modulation in comparison to the spin pumping effect which is reconfirmed from the unchanged damping constant with the variation of Cu spacer layer thickness inserted between W and CoFeB. The giant interfacial spin transparency and its strong dependence on crystal structures of W will be important for future spin-orbitronic devices based on pure spin current.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available