Results in Physics (Jun 2021)
Coherence length versus transition temperature of hydride-based and room temperature superconductors
Abstract
Recent discoveries of carbon-sulfur-hydrogen (C-S-H) room temperature superconductor (287.7 K) and near room temperature in hydride-based materials under high pressure have opened up an interesting and new avenue in the field of superconductivity. One of the important parameters of a superconductor is the coherence length, ξ which is the variation in the density of superconducting phase. ξ can also be related to the characteristic Cooper pair size. In this paper we report on the relation between ξ and the transition temperature, Tc of heavy fermions, conventional, iron arsenide-, cuprate- and hydride-based superconductors. This work showed that the coherence length was large for low Tc but for high Tc, ξ is short and tends to reach saturation value between 15 and 30 Å. ξ of the newly discovered hydride superconductors was found to be in the range of the cuprates. In this work, the coherence length of a 300 K superconductor extrapolated from the hydride-based data was found to be around 15 Å. This coherence length is sufficiently large to allow an effective Coulombic attraction between electrons in a Cooper pair.
