Efficient spin transport across a disordered interface in a low damping magnetic insulator/heavy metal bilayer

S S. P. Alaei (Department of Physics, Stanford University 1 , Stanford, California 94305,) R R. Raj (Department of Chemical Engineering and Materials Science, University of Minnesota 3 , Minneapolis, Minnesota 55455,) S S. Channa (Department of Physics, Stanford University 1 , Stanford, California 94305,) L L. Takana (Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,) D D. O'Mahoney (Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,) X X. Y. Zheng (Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,) E E. E. Fleck (Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,) T T.-Y. Chen (Department of Physics, Center for Quantum Phenomena, New York University 6 , New York, New York 10003,) Z Z. Galazka (Leibniz-Institut für Kristallzüchtung 7 , Max-Born-Str. 2, 12489 Berlin,) A A. D. Kent (Department of Physics, Center for Quantum Phenomena, New York University 6 , New York, New York 10003,) K K. A. Mkhoyan (Department of Chemical Engineering and Materials Science, University of Minnesota 3 , Minneapolis, Minnesota 55455,) Y Y. Suzuki (Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,)

Abstract

We demonstrate efficient spin transfer across a disordered interfacial layer that forms in low damping ferrimagnetic insulator lithium aluminum ferrite (LAFO) and tantalum bilayers. Despite the interfacial disorder, confirmed by transmission electron microscopy, we find a room temperature interfacial spin mixing conductance on the order of 1014 Ω−1m−2 similar to other LAFO-based bilayers with epitaxial interfaces. Broadband ferromagnetic resonance measurements confirm a linewidth broadening in LAFO following the addition of a Ta layer, consistent with the effects of spin pumping. Furthermore, the presence of spin current generated in the Ta layer by spin pumping is confirmed with inverse spin Hall effect measurements. Measurements of the Ta thickness dependence of the spin Hall magnetoresistance and the Gilbert damping enhancement indicate that the Ta spin diffusion length is on the order of 1 nm. This work not only provides a surprising example of efficient spin transport across a disordered interface but also demonstrates the potential for low damping spinel ferrites as a robust system for efficient spin wave spintronics.

Article Details

Volume / Issue Vol. 127, Issue 26
Published December 29, 2025
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (12)

S

S. P. Alaei

Department of Physics, Stanford University 1 , Stanford, California 94305,

R

R. Raj

Department of Chemical Engineering and Materials Science, University of Minnesota 3 , Minneapolis, Minnesota 55455,

S

S. Channa

Department of Physics, Stanford University 1 , Stanford, California 94305,

L

L. Takana

Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,

D

D. O'Mahoney

Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,

X

X. Y. Zheng

Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,

E

E. E. Fleck

Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,

T

T.-Y. Chen

Department of Physics, Center for Quantum Phenomena, New York University 6 , New York, New York 10003,

Z

Z. Galazka

Leibniz-Institut für Kristallzüchtung 7 , Max-Born-Str. 2, 12489 Berlin,

A

A. D. Kent

Department of Physics, Center for Quantum Phenomena, New York University 6 , New York, New York 10003,

K

K. A. Mkhoyan

Department of Chemical Engineering and Materials Science, University of Minnesota 3 , Minneapolis, Minnesota 55455,

Y

Y. Suzuki

Geballe Laboratory for Advanced Materials, Stanford University 2 , Stanford, California 94305,