Abstract
For an infinite Kitaev chain with an impurity described by a deltalike potential, we analytically prove that two overlapping Majorana bound states in a topologically trivial phase in the case of a small superconducting gap exist under the condition V0 = 2Δ, where V0 is the value of the potential and Δ is the superconducting order parameter. For a semi-infinite Kitaev chain with an impurity in the case of a small gap, we prove that there are two overlapping Majorana bound states in the trivial phase and one Majorana bound state in the topological phase and that the Majorana bound state in the latter case is stable under changes in the model parameters. We find explicit analytic expressions for the corresponding wave functions in all cases.
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This research was supported in part by the Ural Branch of the Russian Academy of Sciences (Grant No. 18-2-2-12).
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 200, No. 1, pp. 137–146, July, 2019.
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Tinyukova, T.S., Chuburin, Y.P. Majorana States Near an Impurity in the Kitaev Infinite and Semi-Infinite Model. Theor Math Phys 200, 1043–1052 (2019). https://doi.org/10.1134/S0040577919070080
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DOI: https://doi.org/10.1134/S0040577919070080