• Current Applied Physics
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• v.18 no.11
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• pp.1190-1195
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• 2018

By employing soft X-ray magnetic circular dichroism (XMCD), soft X-ray absorption spectroscopy (XAS), and photoemission spectroscopy (PES), we have investigated the electronic structure of the candidate zero-moment half-metallic $Mn_3Ga$. We have studied the ball-milled and annealed $Mn_3Ga$ powder samples that exhibit nearly zero magnetization. Mn 2p XAS revealed that Mn ions in $Mn_3Ga$ are nearly divalent for both of the Mn ions having the locally octahedral symmetry and those having the locally tetrahedral symmetry. The measured Mn 2p XMCD spectrum of $Mn_3Ga$ is very similar to that of ferrimagnetic $MnFe_2O_4$ having divalent Mn ions. The sum-rule analysis of the Mn 2p XMCD spectrum shows that both the spin and orbital magnetic moments of Mn ions in $Mn_3Ga$ are negligibly small, in agreement with the nearly compensated-ferrimagnetic ground state of $Mn_3Ga$. The valence-band PES spectrum of $Mn_3Ga$ agrees well with the calculated density of states, supporting the half-metallic electronic structure of $Mn_3Ga$.

• Journal of the Korean Magnetics Society
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• v.26 no.6
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• pp.185-189
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• 2016

By employing photoemission spectroscopy (PES) and soft X-ray absorption spectroscopy (XAS), the electronic structure of the candidate half-metallic antiferromagnet of $Mn_3Ga$ Heusler compound has been investigated. We have studied two ball-milled $Mn_3Ga$ powder samples, one after annealing and the other without annealing, respectively. Based on the Mn 2p XAS study, we have found that Mn ions are nearly divalent in $Mn_3Ga$ and that the Mn ions having the locally octahedral symmetry and those having the locally tetrahedral symmetry are both present in $Mn_3Ga$. We have found relatively good agreement between the measured valence-band PES spectrum of $Mn_3Ga$ and the calculated density of states, which is in agreement with the half-metallic electronic structure of $Mn_3Ga$.