Spin Hall Effect and Its Inverse

Spin Hall effect (SHE) was predicted by Mikhail D’yakonov and Vladimir Pere [1] in 1971 and experimentally demonstrated by Valenzuela and Tinkham [3] in 2006 through Inverse spin hall measurement (ISHE), is one of the ways to manipulate the magnetization in a magnetic layer. In the SHE, the application of charge currents generates a transverse spin current due to spin-orbit interactions. On the other hand, in the ISHE measurement, spin current is injected into a non-magnetic metal from the ferromagnetic material (via a phenomenon known as spin pumping) and then detected by making contact on non-magnetic layer as the charge current. Our research interests are in the study of SHE and spin-orbit torque in different ferromagnet/non-magnet bilayers or trilayer structures using ferromagnetic resonance. We are developing an optical and an electrical method for detection of spin currents in different NM materials. We are also using a technique called spin torque ferromagnetic resonance for quantification of spin Hall angle.

Schematic for spin Hall effect.

Schematic for Inverse spin Hall effect.

[1] Yaroslav Tserkovnyak and Arne Brataas and Gerrit E. W. Bauer, Phys. Rev. Lett. 88, 117601 (2002).

[2] M. I. Dyakonov and V. I. Perel, Phys. Rev. Lett. A35, 459 (1971).

[3] Valenzuela, S O and Tinkham, M, Nature 442, 176 (2006).

Our publications in this area:

Antidamping spin-orbit torques in epitaxial-Py(100)/β-Ta (Editor's Pick), Dhananjay Tiwari, Nilamani Behera, Akash Kumar, Philipp Dürrenfeld, Sujeet Chaudhary, D. K. Pandya, Johan Åkerman, and P. K. Muduli, Appl. Phys. Lett. 111, 232407 (2017).
Crystalline phase dependent spin current efficiency in sputtered Ta thin films, Rajni Bansal, Nilamani Behera, Akash Kumar, and P. K. Muduli, Appl. Phys. Lett. 110, 202402 (2017).
Large spin current generation by the spin Hall effect in mixed crystalline phase Ta thin films, Akash Kumar, Rajni Bansal, Sujeet Chaudhary, and P. K. Muduli , Phys. Rev. B 98, 104403 (2018).
Large Spin Hall Angle in beta-W Thin Films Grown on CoFeB without Oxygen Plasma, Rajni Bansal, Gurudeo Nirala, Akash Kumar, Sujeet Chaudhary and P. K. Muduli, SPIN, 8, 1850018 (2018).
Large Spin-To-Charge Conversion at the Two-Dimensional Interface of Transition-Metal Dichalcogenides and Permalloy, Himanshu Bangar, Akash Kumar, Niru Chowdhury, Richa Mudgal, Pankhuri Gupta, Ram Singh Yadav, Samaresh Das, and Pranaba Kishor Muduli, ACS Appl. Mater. Interfaces 14, 41598 (2022).