Pressured-induced superconducting phase with large upper critical field and concomitant enhancement of antiferromagnetic transition in EuTe(2)

We report an unusual pressure-induced superconducting state that coexists with an antiferromagnetic ordering of Eu(2+) moments and shows a large upper critical field comparable to the Pauli paramagnetic limit in EuTe(2). In concomitant with the emergence of superconductivity with T(c) ≈ 3–5 K above P(c) ≈ 6 GPa, the antiferromagnetic transition temperature T(N)(P) experiences a quicker rise with the slope increased dramatically from dT(N)/dP = 0.85(14) K/GPa for P ≤ P(c) to 3.7(2) K/GPa for P ≥ P(c). Moreover, the superconducting state can survive in the spin-flop state with a net ferromagnetic component of the Eu(2+) sublattice under moderate magnetic fields μ(0)H ≥ 2 T. Our findings establish the pressurized EuTe(2) as a rare magnetic superconductor possessing an intimated interplay between magnetism and superconductivity.