Unconventional resistive transitions in the extreme type-II superconductor Tl2Mo6Se6

A. PETROVIC; YANINA FASANO; R. LORTZ; M. DECROUX; M. POTEL; R. CHEVREL; Ø. FISCHER

PHYSICA C - SUPERCONDUTIVITY

Año: 2007 vol. 460 p. 702 - 703

0921-4534

A study of the resistive transition into the superconducting state of the quasi-1D superconductor Tl2Mo6Se6 (Tc = 5 K) has revealed a broadening effect under applied magnetic field similar to that seen in the high-Tc cuprates. Using anisotropic Ginzburg¨CLandau theory we calculate a Ginzburg number Gi ¡Ö 1.8 ¡Á 10−5, corresponding to a critical region of width 0.09 mK, which is 18 000 times smaller than the measured ¦¤Tc2. This proves that fluctuations of the order parameter are not the predominant factor responsible for the broadening of the transition and suggests the possible absence of a macroscopic phase coherence over a wide region of the vortex phase diagram.