%0 Journal Article
%T On the Role of Chemical Potential in Determining the Temperature Dependent Critical Magnetic Field and the Penetration Depth of Superconductors
%A Gulshan Prakash Malik
%A Vijaya Shankar Varma
%J World Journal of Condensed Matter Physics
%P 96-106
%@ 2160-6927
%D 2024
%I Scientific Research Publishing
%R 10.4236/wjcmp.2024.144009
%X Dealing with both elemental and high-<i>T</i><i><sub>c</sub></i> superconductors (SCs) - Sn, Nb and Pb belonging to the former category, and MgB<sub>2</sub> and different samples of YBCO to the latter - we show that the difference in the values of their critical magnetic field <i>H</i><i><sub>c</sub></i><sub>1,</sub><i><sub>c</sub></i><sub>2</sub> and the penetration depth <i>&#955;</i><i><sub>L</sub></i>(0) is, remarkably, attributable predominantly to the difference in the values of a single parameter, viz., the chemical potential (<i>&#956;</i>) close to their critical temperatures (<i>T</i><i><sub>c</sub></i>s). Based directly on the dynamics of pairing in a magnetic field and the corresponding number equation, our approach relates <i>H</i><i><sub>c</sub></i><sub>1,</sub><i><sub>c</sub></i><sub>2</sub> of an SC with the following set of its properties: <i>S</i><sub>1</sub> = {<i>&#956;</i>, <i>T</i><i><sub>c</sub></i>, <i>Debye temperature</i>, <i>effective mass of the electron</i>, <i>magnetic interaction parameter</i>, <i>Landau index</i>}. Hence, it provides an alternative to the approach followed by Talantsev [Mod. Phys. Lett. B <b>33</b>, 1950195 (2019)] who has shown by ingeniously combining the results of various well-established theories that <i>H</i><i><sub>c</sub></i><sub>2</sub> of an SC can be calculated via four different equations, each of which invokes two or more properties from its sample-specific set <i>S</i><sub>2</sub> = {<i>T</i><i><sub>c</sub></i>, <i>gap</i>, <i>coherence length</i>, <i>&#955;</i><i><sub>L</sub></i>(0), <i>jump in sp. ht.</i>}, which is radically different from <i>S</i><sub>1</sub>.
%K Pairing and Number Equations Incorporating Temperature
%K Chemical Potential and Magnetic Field
%K Critical Magnetic Field
%K Penetration Depth
%K Sn
%K Nb
%K Pb
%K MgB<sub>2</sub>
%K YBCO
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=137780