%A Ryszard Gonczarek, Mateusz Krzyzosiak, Adam Gonczarek, Lucjan Jacak %T Analytical assessment of some characteristic ratios for s-wave superconductors %0 Journal Article %D 2018 %J Front. Phys. %J Frontiers of Physics %@ 2095-0462 %R 10.1007/s11467-017-0739-x %P 137403- %V 13 %N 2 %U {https://journal.hep.com.cn/fop/EN/10.1007/s11467-017-0739-x %8 2018-04-01 %X

We evaluate some thermodynamic quantities and characteristic ratios that describe low- and hightemperature s-wave superconducting systems. Based on a set of fundamental equations derived within the conformal transformation method, a simple model is proposed and studied analytically. After including a one-parameter class of fluctuations in the density of states, the mathematical structure of the s-wave superconducting gap, the free energy difference, and the specific heat difference is found and discussed in an analytic manner. Both the zero-temperature limit T = 0 and the subcritical temperature range TTc are discussed using the method of successive approximations. The equation for the ratio R1, relating the zero-temperature energy gap and the critical temperature, is formulated and solved numerically for various values of the model parameter. Other thermodynamic quantities are analyzed, including a characteristic ratio R2, quantifying the dynamics of the specific heat jump at the critical temperature. It is shown that the obtained model results coincide with experimental data for low-Tc superconductors. The prospect of application of the presented model in studies of high-Tc superconductors and other superconducting systems of the new generation is also discussed.