TY - JOUR
T1 - Collective spin dynamics under dissipative spin Hall torque
AU - Tserkovnyak, Yaroslav
AU - Maniv, Eran
AU - Analytis, James G.
N1 - Funding Information:
This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences under Award No. DE-SC0012190.
Publisher Copyright:
© 2021 Author(s).
PY - 2021/1/18
Y1 - 2021/1/18
N2 - Current-induced spin torques in layered magnetic heterostructures have many commonalities across broad classes of magnetic materials. These include not only collinear ferromagnets, ferrimagnets, and antiferromagnets but also more complex noncollinear spin systems. We develop a general Lagrangian-Rayleigh approach for studying the role of dissipative torques, which can pump energy into long-wavelength magnetic dynamics, causing dynamic instabilities. While the Rayleigh structure of such torques is similar for different magnetic materials, their consequences depend sensitively on the nature of the order and, in particular, on whether there is a net magnetic moment. The latter endows the system with a unipolar switching capability, while magnetically compensated materials tend to evolve toward limit cycles, at large torques, with chirality dependent on the torque sign. Apart from the ferromagnetic and antiferromagnetic cases, we discuss ferrimagnets, which display an intricate competition between switching and limit cycles. As a simple case for compensated noncollinear order, we consider isotropic spin glasses and a scenario of their coexistence with a collinear magnetic order.
AB - Current-induced spin torques in layered magnetic heterostructures have many commonalities across broad classes of magnetic materials. These include not only collinear ferromagnets, ferrimagnets, and antiferromagnets but also more complex noncollinear spin systems. We develop a general Lagrangian-Rayleigh approach for studying the role of dissipative torques, which can pump energy into long-wavelength magnetic dynamics, causing dynamic instabilities. While the Rayleigh structure of such torques is similar for different magnetic materials, their consequences depend sensitively on the nature of the order and, in particular, on whether there is a net magnetic moment. The latter endows the system with a unipolar switching capability, while magnetically compensated materials tend to evolve toward limit cycles, at large torques, with chirality dependent on the torque sign. Apart from the ferromagnetic and antiferromagnetic cases, we discuss ferrimagnets, which display an intricate competition between switching and limit cycles. As a simple case for compensated noncollinear order, we consider isotropic spin glasses and a scenario of their coexistence with a collinear magnetic order.
UR - http://www.scopus.com/inward/record.url?scp=85099787647&partnerID=8YFLogxK
U2 - 10.1063/5.0035586
DO - 10.1063/5.0035586
M3 - Article
AN - SCOPUS:85099787647
VL - 118
JO - Applied Physics Letters
JF - Applied Physics Letters
SN - 0003-6951
IS - 3
M1 - 032406
ER -