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arXiv · 2104.06171

Atomic Manipulation of In-gap States on the $\beta$-Bi$_2$Pd Superconductor

Cristina Mier·Jiyoon Hwang·Jinkyung Kim·Yujeong Bae·Fuyuki Nabeshima·Yoshinori Imai·Atsutaka Maeda·Nicolás Lorente·Andreas Heinrich·Deung-Jang Choi
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Abstract

Electronic states in the gap of a superconductor inherit intriguing many-body properties from the superconductor. Here, we create these in-gap states by manipulating Cr atomic chains on the $\beta$-Bi$_2$Pd superconductor. We find that the topological properties of the in-gap states can greatly vary depending on the crafted spin chain. These systems make an ideal platform for non-trivial topological phases because of the large atom-superconductor interactions and the existence of a large Rashba coupling at the Bi-terminated surface. We study two spin chains, one with atoms two-lattice-parameter apart and one with square-root-of-two lattice parameters. Of these, only the second one is in a topologically non-trivial phase, in correspondence with the spin interactions for this geometry.

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Cristina Mier, Jiyoon Hwang, Jinkyung Kim, Yujeong Bae, Fuyuki Nabeshima, Yoshinori Imai, Atsutaka Maeda, Nicolás Lorente, Andreas Heinrich, Deung-Jang Choi. 2021-04-13. Atomic Manipulation of In-gap States on the $\beta$-Bi$_2$Pd Superconductor. https://doi.org/10.1103/physrevb.104.045406

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