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Infrared spectroscopy under multi-extreme conditions: Direct observation of pseudo gap formation and collapse in CeSb

T. Nishi·S. Kimura·T. Takahashi·Y. Mori·Y. S. Kwon·H. J. Im·H. Kitazawa
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Abstract

Infrared reflectivity measurements of CeSb under multi-extreme conditions (low temperatures, high pressures and high magnetic fields) were performed. A pseudo gap structure, which originates from the magnetic band folding effect, responsible for the large enhancement in the electrical resistivity in the single-layered antiferromagnetic structure (AF-1 phase) was found at a pressure of 4 GPa and at temperatures of 35 - 50 K. The optical spectrum of the pseudo gap changes to that of a metallic structure with increasing magnetic field strength and increasing temperature. This change is the result of the magnetic phase transition from the AF-1 phase to other phases as a function of the magnetic field strength and temperature. This result is the first optical observation of the formation and collapse of a pseudo gap under multi-extreme conditions.

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T. Nishi, S. Kimura, T. Takahashi, Y. Mori, Y. S. Kwon, H. J. Im, H. Kitazawa. 2005-04-18. Infrared spectroscopy under multi-extreme conditions: Direct observation of pseudo gap formation and collapse in CeSb. https://doi.org/10.1103/physrevb.71.220401

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