The emerging altermagnetic RuO_(2)with both compensated magnetic moments and broken time-reversal symmetry possesses nontrivial magneto-electronic responses and nonrelativistic spin currents that are closely related t...The emerging altermagnetic RuO_(2)with both compensated magnetic moments and broken time-reversal symmetry possesses nontrivial magneto-electronic responses and nonrelativistic spin currents that are closely related to the magnetic easy axis.Ru M_(3)-edge X-ray magnetic linear dichroism(XMLD)measurements were performed to probe the Néel order in RuO_(2).For epitaxial RuO_(2) films,characteristic XMLD signals were observed for either RuO_(2)(100)or RuO_(2)(110)at normal incidence or RuO_(2)(001)at oblique incidence.The signals disappeared when the test temperature exceeded the Néel temperature.For non-epitaxial RuO_(2) films,the flat lines in the XMLD patterns of RuO_(2)(100)and RuO_(2)(110)demonstrate that there is no in-plane uniaxial alignment of the Néel order in these samples because of the counterbalanced Néel order of the twin crystals,as evidenced by X-ray diffraction phi-scan measurements.Our experimental results unambiguously demonstrate antiferromagnetism in RuO_(2) films and reveal the spatial relation of the Néel order parallel to the RuO_(2)[001]crystalline axis.These findings deepen the understanding of RuO_(2) and other attractive altermagnetic materials used in the field of spintronics.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12241404,52225106,and 523B1007)Open Fund of the State Key Laboratory of Spintronics Devices and Technologies(Grant No.SPL-2401)。
文摘The emerging altermagnetic RuO_(2)with both compensated magnetic moments and broken time-reversal symmetry possesses nontrivial magneto-electronic responses and nonrelativistic spin currents that are closely related to the magnetic easy axis.Ru M_(3)-edge X-ray magnetic linear dichroism(XMLD)measurements were performed to probe the Néel order in RuO_(2).For epitaxial RuO_(2) films,characteristic XMLD signals were observed for either RuO_(2)(100)or RuO_(2)(110)at normal incidence or RuO_(2)(001)at oblique incidence.The signals disappeared when the test temperature exceeded the Néel temperature.For non-epitaxial RuO_(2) films,the flat lines in the XMLD patterns of RuO_(2)(100)and RuO_(2)(110)demonstrate that there is no in-plane uniaxial alignment of the Néel order in these samples because of the counterbalanced Néel order of the twin crystals,as evidenced by X-ray diffraction phi-scan measurements.Our experimental results unambiguously demonstrate antiferromagnetism in RuO_(2) films and reveal the spatial relation of the Néel order parallel to the RuO_(2)[001]crystalline axis.These findings deepen the understanding of RuO_(2) and other attractive altermagnetic materials used in the field of spintronics.
