Resistivity and electron-phonon coupling in YNi2B2C single crystals

Abstract

In this work, we present the results of precise measurements of the resistivity of YNi2B2C single crystals with Tc = 15.5 K as a function of the temperature, and analyze the experimental data in the framework of the BlochGrüneisen theory and electron-phonon coupling. The transport electron-phonon spectral function that best fits the resistivity data is then inserted in the real-axis Eliashberg equations, which are directly solved to determine the normalized tunneling conductance both in s-and d-wave symmetry.

The Thermodynamic Critical Field οf YNi2B2C Superconductor

“…1) [3]. In most cases [α 2 F (Ω )] tr does not differ too much from the ordinary Eliashberg function.…”

“…In the presented calculations µ * = 0 was assumed (in accordance with an analysis presented in [3]). …”

“…From the physical point of view, the YNi 2 B 2 C compound is interesting due to its relatively high value of the critical temperature T C ≈ 15 K [3,4]. Additionally, it still remains unclear whether YNi 2 B 2 C is conventional or exotic superconductor.…”

The Properties of the Superconducting State in YNi2B2C: The One-Band Eliashberg Approach

“…On the other hand, some researchers basing on the thermal and spectroscopic experiments are moving toward the direction of the one-band models with a non-trivial wave symmetry (s + g or even d-wave symmetry) [15][16][17][18]. The issue is clouding by the fact that the calculations conducted till the present day for the one-band Eliashberg model were (863) not strict; the studies were based on very simplified form of the Eliashberg function [19] or approximated analytical formulae [20].…”

“…where the transport function ([α 2 F (Ω )] tr ) was determined by Gonnelli et al in [19] (for details see also [10]). …”