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arXiv · 1203.4182

Continuous Transition between Antiferromagnetic Insulator and Paramagnetic Metal in the Pyrochlore Iridate Eu2Ir2O7

Jun J. Ishikawa·Eoin C. T. O'Farrell·Satoru Nakatsuji
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Abstract

Our single crystal study of the magneto-thermal and transport properties of the pyrochlore iridate Eu2Ir2O7 reveals a continuous phase transition from a paramagnetic metal to an antiferromagnetic insulator for a sample with stoichiometry within ~1% resolution. The insulating phase has strong proximity to an antiferromagnetic semimetal, which is stabilized by several % level of the off-stoichiometry. Our observations suggest that in addition to electronic correlation and spin-orbit coupling the magnetic order is essential for opening the charge gap.

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Jun J. Ishikawa, Eoin C. T. O'Farrell, Satoru Nakatsuji. 2012-03-19. Continuous Transition between Antiferromagnetic Insulator and Paramagnetic Metal in the Pyrochlore Iridate Eu2Ir2O7. https://doi.org/10.1103/physrevb.85.245109

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