Tunneling Magnetoresistance in Altermagnetic <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi>RuO</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> </mml:mrow> </mml:math> -Based Magnetic Tunnel Junctions
Seunghyeon Noh, Gye-Hyeon Kim, Jiyeon Lee, Hyeonjung Jung, Uihyeon Seo, Gimok So, Jaebyeong Lee, Seunghyun Lee, Miju Park, Seungmin Yang, Yoon Seok Oh, Hosub Jin, Changhee Sohn, Jung‐Woo Yoo
Abstract
Altermagnets exhibit characteristics akin to antiferromagnets, with spin-split anisotropic bands in momentum space. RuO_{2} has been considered as a prototype altermagnet; however, recent reports have questioned altermagnetic ground state in this material. In this Letter, we demonstrate spin-dependent tunneling magnetoresistance (TMR) in RuO_{2}-based magnetic tunnel junctions, which suggests the spin-splitted anisotropic band structure of our RuO_{2} films. The observed TMR is contingent on the direction of the Néel vector of RuO_{2} and reverse its sign by the inversion of the Néel vector. These results reflect the altermagnetic nature of RuO_{2} and highlight its potential for spintronic applications, leveraging the combined strengths of ferromagnetic and antiferromagnetic systems.