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arXiv · 1902.09133

$^{77}$Se-NMR Study under Pressure on 12%-S Doped FeSe

Takanori Kuwayama·Kohei Matsuura·Yuta Mizukami·Shigeru Kasahara·Yuji Matsuda·Takasada Shibauchi·Yoshiya Uwatoko·Naoki Fujiwara
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Abstract

The 12%-S doped FeSe system has a high Tc of 30 K at a pressure of 3.0 GPa. We have successfully investigated its microscopic properties for the first time via $^{77}$Se-NMR measurements under pressure. The antiferromagnetic (AFM) fluctuations at the optimal pressure (~3 GPa) exhibited unexpected suppression compared with the AFM fluctuations at ambient pressure, even though the optimal pressure is close to the phase boundary of the AFM phase induced at the high-pressure region. In addition, we revealed that the SC phase at an applied field of 6.02 T exhibited a remarkable double-dome structure in the pressure-temperature phase diagram, unlike the SC phase at zero field.

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Takanori Kuwayama, Kohei Matsuura, Yuta Mizukami, Shigeru Kasahara, Yuji Matsuda, Takasada Shibauchi, Yoshiya Uwatoko, Naoki Fujiwara. 2019-02-25. $^{77}$Se-NMR Study under Pressure on 12%-S Doped FeSe. https://doi.org/10.7566/jpsj.88.033703

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