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تسجيل مستخدم جديدNovel self-epitaxy for inducing superconductivity in the topological insulator (Bi1-xSbx)2Te3
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Using the superconducting proximity effect for engineering a topological superconducting state in a topological insulator (TI) is a promising route to realize Majorana fermions. However, epitaxial growth of a superconductor on the TI surface to achieve a good proximity effect has been a challenge. We discovered that simply depositing Pd on thin films of the TI material (Bi$_{1-x}$Sb$_x$)$_2$Te$_3$ leads to an epitaxial self-formation of PdTe$_2$ superconductor having the superconducting transition temperature of ~1 K. This self-formed superconductor proximitizes the TI, which is confirmed by the appearance of a supercurrent in Josephson-junction devices made on (Bi$_{1-x}$Sb$_x$)$_2$Te$_3$. This self-epitaxy phenomenon can be conveniently used for fabricating TI-based superconducting nanodevices to address the superconducting proximity effect in TIs.
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When a topological insulator (TI) is made into a nanowire, the interplay between topology and size quantization gives rise to peculiar one-dimensional (1D) states whose energy dispersion can be manipulated by external fields. With proximity-induced s
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