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arXiv · 1808.05309

Significant change in the electronic behavior associated with structural distortions in the single crystalline SrAg4As2

Bing Shen·Eve Emmanouilidou·Xiaoyu Deng·Alix McCollam·Jie Xing·Gabriel Kotliar·Amalia I. Coldea·Ni Ni
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Abstract

We report a combined study of transport and thermodynamic measurements on the layered pnictide material SrAg4As2. Upon cooling, a drop in electrical and Hall resistivity, a jump in heat capacity and an increase in susceptibility and magnetoresistance (MR) are observed around 110 K. These observations suggest that non-magnetic phase transitions emerge at around 110 K, that are likely associated with structural distortions. In sharp contrast with the first-principles calculations based on the crystal structure at room temperature, quantum oscillations reveal small Fermi pockets with light effective masses, suggesting a significant change in the Fermi surface topology caused by the low temperature structural distortion. No superconductivity emerges in SrAg$_4$As$_2$ down to 2 K and under pressures up to 2.13 GPa; instead, the low temperature structural distortion increases linearly with temperature at a rate of ~13 K/GPa above 0.89 GPa.

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Bing Shen, Eve Emmanouilidou, Xiaoyu Deng, Alix McCollam, Jie Xing, Gabriel Kotliar, Amalia I. Coldea, Ni Ni. 2018-11-30. Significant change in the electronic behavior associated with structural distortions in the single crystalline SrAg4As2. https://doi.org/10.1103/physrevb.98.235130

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