The pressure effect on the newly discovered charge-transferred BiS2-based superconductor, Eu3Bi2S4F4, with a Tc of 1.5 K at ambient pressure, is investigated by transport and magnetic measurements. Accompanied with the enhancement of metallicity under pressures, the onset superconducting transition temperature increases abruptly around 1.0 GPa, reaching ∼10.0 K at 2.26 GPa. AC magnetic susceptibility measurements indicate that a new superconducting phase with a higher Tc emerges and dominates at high pressures. In the broad pressure window of 0.68 GPa≤p≤2.00 GPa, the high-Tc phase coexists with the low-Tc phase. Hall effect measurements reveal a significant difference in electronic structures between the two superconducting phases. Our work devotes the effort to establish the commonality of pressure effect on the BiS2-based superconductors, and also uncovers the importance of electron carrier density in the high-Tc phase.
@article{arxiv.1412.5446,
title = {Pressure-enhanced superconductivity in Eu$_3$Bi$_2$S$_4$F$_4$},
author = {Yongkang Luo and Hui-Fei Zhai and Pan Zhang and Zhu-An Xu and Guang-Han Cao and J. D. Thompson},
journal= {arXiv preprint arXiv:1412.5446},
year = {2014}
}