Summary: | Recently, several research groups have reported on anomalous enhancement of the self-field critical currents, <i>I<sub>c</sub></i>(sf,<i>T</i>), at low temperatures in superconductor/Dirac-cone material/superconductor (S/DCM/S) junctions. Some papers attributed the enhancement to the low-energy Andreev bound states arising from winding of the electronic wave function around DCM. In this paper, <i>I<sub>c</sub></i>(sf,<i>T</i>) in S/DCM/S junctions have been analyzed by two approaches: modified Ambegaokar-Baratoff and ballistic Titov-Beenakker models. It is shown that the ballistic model, which is traditionally considered to be a basic model to describe <i>I<sub>c</sub></i>(sf,<i>T</i>) in S/DCM/S junctions, is an inadequate tool to analyze experimental data from these type of junctions, while Ambegaokar-Baratoff model, which is generally considered to be a model for <i>I<sub>c</sub></i>(sf,<i>T</i>) in superconductor/insulator/superconductor junctions, provides good experimental data description. Thus, there is a need to develop a new model for self-field critical currents in S/DCM/S systems.
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