Antiferromagnetic Switching Driven by the Collective Dynamics of a Coexisting Spin Glass
Eran Maniv, Nityan Nair, Shannon C. Haley, Spencer Doyle, Caolan John, Stefano Cabrini, Ariel Maniv, Sanath K. Ramakrishna, Yun-Long Tang, Peter Ercius, Ramamoo… 展开作者
Eran Maniv, Nityan Nair, Shannon C. Haley, Spencer Doyle, Caolan John, Stefano Cabrini, Ariel Maniv, Sanath K. Ramakrishna, Yun-Long Tang, Peter Ercius, Ramamoorthy Ramesh, Yaroslav Tserkovnyak, Arneil P. Reyes, James G. Analytis
备注：
7 pages, 4 Figures, supplement available on reasonable request
发表信息：
Science Advances 08 Jan 2021: Vol. 7, no. 2, eabd8452
The theory behind the electrical switching of antiferromagnets is premised on the existence of a well defined broken symmetry state that can be rotated to encode information. A spin glass is in many ways the antithesis of this state, characterized by an ergodic landscape of nearly degenerate magnetic configurations, choosing to freeze into a distribution of these in a manner that is seemingly bereft of information. In this study, we show that the coexistence of spin glass and antiferromagnetic order allows a novel mechanism to facilitate the switching of the antiferromagnet Fe$_{1/3+δ}$NbS$_2$, which is rooted in the electrically-stimulated collective winding of the spin glass. The local texture of the spin glass opens an anisotropic channel of interaction that can be used to rotate the equilibrium orientation of the antiferromagnetic state. The use of a spin glass' collective dynamics to electrically manipulate antiferromagnetic spin textures has never been applied before, opening the field of antiferromagnetic spintronics to many more material platforms with complex magnetic textures.
Conversion of glassy antiferromagnetic-insulating phase to equilibrium ferromagnetic-metallic phase by devitrification and recrystallization in Al substituted Pr${_{0.5}}$Ca$_{0.5}$MnO${_3}$
结果表明，Pr ${_{0.5}}$ Ca $_{0.5}$ MnO ${_3}$和La ${_{0.5}}$ Ca $_{0.5}$ MnO ${_3}$（LCMO）在低温下表现出定性相似且明显异常的M-H曲线。在磁场作用下，两种材料都发生了一个宽的一阶不可逆的反铁磁（AF）-绝缘（I）-铁磁（FM）-金属（M）相变，并产生了软FM态。而Pr $_{0.5}$ Ca $_{0.5}$ Mn $_{0.975}$ Al $_{0.025}$ O $_3$（PCMAO）的低温平衡态为FM-M，而LCMO的低温平衡态为AF-I。在这两个系统中，各自的平衡相共存的另一个阶段与相反的顺序，这是不平衡的，和冷却场可以调整的分数共存相。它表明较早的共存FM-M相的行为像“磁性玻璃”在LCMO。在这里，我们表明，从专门设计的测量协议的AF-I相的PCMAO具有磁性玻璃态的所有特征。它在加热时失透，并且在退火后再结晶为平衡FM-M相。这种玻璃状的AF-I相也显示出类似的有趣的功能，观察到在FM-M磁性玻璃态的LCMO，当开始共存的玻璃分数较大，连续退火的结果在较大的平衡相的分数。两个锰氧化物系统之间的这种相似性，与各自的玻璃相和平衡相的对比磁顺序指向一个可能的普遍性。
Antiferromagnetic spintronics is one of the leading candidates for next-generation electronics. Among abundant antiferromagnets, noncollinear antiferromagnets are promising for achieving practical applications due to coexisting ferromagnetic and antiferromagnetic merits. In this perspective, we briefly review the recent progress in the emerging noncollinear antiferromagnetic spintronics from fundamental physics to device applications. Current challenges and future research directions for this field are also discussed.
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ShanghaiTech University（上海科技大学）；Shanghai Advanced Research Institute, Chinese Academy of Sciences（中国科学院上海高等研究院）；Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；University of Chinese Academy of Sciences（中国科学院大学）
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