Crystal growth and ambient and high pressure study of the reentrant superconductor Tm_2Fe_3Si_5

Abstract

We report single crystal growth of the reentrant superconductor Tm_2Fe_3Si_5, and measurements of the anisotropic static magnetic susceptibility χ(T) and isothermal magnetization M(H), ac susceptibility χ_ac(T), electrical resistivity ρ(T) and heat capacity C(T) at ambient pressure and χ_ac(T) at high pressure. The magnetic susceptibility along the c-axis χ_c(T) shows a small maximum around 250 K and does not follow the Curie-Weiss behavior while the magnetic susceptibility along the a-axis χ_a(T) follows a Curie-Weiss behavior between 130 K and 300 K with a Weiss temperature θand an effective magnetic moment μ_eff which depend on the temperature range of the fit. The easy axis of magnetization is perpendicular to the c-axis and χ_a/χ_c = 3.2 at 1.8 K. The ambient pressure χ_ac(T) and C(T) measurements confirm bulk antiferromagnetic ordering at T_N = 1.1 K. The sharp drop in χ_ac below T_N is suggestive of the existence of a spin-gap. We observe superconductivity only under applied pressures P\geq 2 kbar. The temperature-pressure phase diagram showing the non-monotonic dependence of the superconducting transition temperature T_c on pressure P is presented.

7 pages, 8 figures