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 SrAg4As2 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.
@article{arxiv.1808.05309,
title = {Significant change in the electronic behavior associated with structural distortions in the single crystalline SrAg4As2},
author = {Bing Shen and Eve Emmanouilidou and Xiaoyu Deng and Alix McCollam and Jie Xing and Gabriel Kotliar and Amalia I. Coldea and Ni Ni},
journal= {arXiv preprint arXiv:1808.05309},
year = {2018}
}