Abstract
Realizing topological superconductivity by integrating high-transition-temperature (TC) superconductors with topological insulators can open new paths for quantum computing applications. Here, a new approach is reported for increasing the superconducting transition temperature (Formula presented.) by interfacing the unconventional superconductor Fe(Te,Se) with the topological insulator Bi–Te system in the low-Se doping regime, near where superconductivity vanishes in the bulk. The critical finding is that the (Formula presented.) of Fe(Te,Se) increases from nominally non-superconducting to as high as 12.5 K when Bi2Te3 is replaced with the topological phase Bi4Te3. Interfacing Fe(Te,Se) with Bi4Te3 is also found to be critical for stabilizing superconductivity in monolayer films where (Formula presented.) can be as high as 6 K. Measurements of the electronic and crystalline structure of the Bi4Te3 layer reveal that a large electron transfer, epitaxial strain, and novel chemical reduction processes are critical factors for the enhancement of superconductivity. This novel route for enhancing TC in an important epitaxial system provides new insight on the nature of interfacial superconductivity and a platform to identify and utilize new electronic phases.
Original language | English |
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Article number | 2401809 |
Journal | Advanced Materials |
Volume | 36 |
Issue number | 31 |
DOIs | |
State | Published - Aug 1 2024 |
Funding
This material was based on work supported by the U.S. Department of Energy, Office of Science, National Quantum Information Sciences Research Centers, Quantum Science Center (spectroscopy), and from U.S. DOE, Office of Science, Basic Energy Sciences, Materials Science and Engineering Division (synthesis, transport and structural characterization). A.R.M. was funded by the NNSA's Laboratory Directed Research and Development Program at Los Alamos National Laboratory. Los Alamos National Laboratory, an affirmative action equal opportunity employer, is managed by Triad National Security, LLC for the U.S. Department of Energy's NNSA, under contract 89233218CNA000001. V.S. effort was sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT\u2010Battelle, LLC, for the U.S. Department of Energy. The authors would like to thank Seongshik Oh, Xiong Yao, Michael McGuire, and Brain Sales for valuable discussions.
Keywords
- molecular beam epitaxy
- quantum materials
- topological materials
- topological superconductor