Pressure dependence of Tc in LnFeAsO1-y (Ln = La, Ce, Nd, Tb)

27th International Conference on Low Temperature Physics

Takeshita, N.^1 ; Miyazawa, K.^1,2 ; Iyo, A.^1,2 ; Furuta, S.^3 ; Mito, M.^3 ; Eisaki, H.^1

National Institute of Advanced Industrial Science and Technology, Ibaraki, Tsukuba

305-8568, Japan^1

Department of Applied Electronics, Tokyo University of Science, Chiba, Noda

27835'0, Japan^2

Faculty of Engineering, Kyushu Institute of Technology, Kitakyushu, Fukuoka

8048550, Japan^3

关键词: Applying pressure;    Bulk superconductivity;    Hydrostatic high pressures;    Monotonic decrease;    Oxygen deficient;    Pressure dependence;    Temperature dependence;    Zero resistivity temperature;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/568/2/022047/pdf
DOI  :  10.1088/1742-6596/568/2/022047

来源: IOP

【 摘 要 】

We measured The temperature dependence of electrical resistivity of non-fluorine- substituted, oxygen-deficient LnFeAsO1-y(Ln La, Ce, Nd, Tb) under hydrostatic high pressure up to '8 GPa in order to observe pressure dependence of superconducting transition temperature Tc. In LaFeAsO0.65, onset Tcinitially enhances below 4 GPa, then decreases by applying further pressure. However, The zero-resistivity temperature does not show enhancement by applying pressure. In The case of NdFeAsO1-yand TbFeAsO1-y, Tcshows monotonic decrease as increasing pressure. Tcis much more likely to go down faster if Ln with small ionic size was taken. Therefore, The bulk superconductivity is suppressed finally at ∼7 GPa in TbFeAsO0.7.