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Over the last decade, the possibility of realizing topological superconductivity (TSC) has generated much excitement. TSC can be created in electronic systems where the topological and superconducting orders coexist, motivating the continued exploration of candidate material platforms to this end. Here, we usemolecular beam epitaxy (MBE) to synthesize heterostructures that host emergent interfacial superconductivity when a non-superconducting antiferromagnet (FeTe) is interfaced with a topological insulator (TI) (Bi, Sb)2Te3. By performing in-vacuo angle-resolved photoemission spectroscopy (ARPES) and ex-situ electrical transport measurements, we find that the superconducting transition temperature and the upper critical magnetic field are suppressed when the chemical potential approaches the Dirac point. We provide evidence to show that the observed interfacial superconductivity and its chemical potential dependence is the result of the competition between the Ruderman-Kittel-Kasuya-Yosida-type ferromagnetic coupling mediated by Dirac surface states and antiferromagnetic exchange couplings that generate the bicollinear antiferromagnetic order in the FeTe layer.
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This content will become publicly available on March 1, 2027
Meissner Effect and Nonreciprocal Charge Transport in Non‐Topological 1T‐CrTe 2 /FeTe Heterostructures
ABSTRACT Interface‐induced superconductivity has recently been achieved by stacking a magnetic topological insulator layer on an antiferromagnetic FeTe layer. However, the mechanism driving this emergent superconductivity remains unclear. Here, we employ molecular beam epitaxy to grow a 1T‐CrTe2layer, a 2D ferromagnet with a Curie temperature up to room temperature, on a FeTe layer. These 1T‐CrTe2/FeTe heterostructures show superconductivity with a critical temperature of ∼12 K. Through magnetic force microscopy measurements, we observe the Meissner effect on the surface of the 1T‐CrTe2layer. Our electrical transport measurements reveal that the 1T‐CrTe2/FeTe heterostructures exhibit nonreciprocal charge transport behavior, characterized by a large magneto‐chiral anisotropy coefficient. The enhanced nonreciprocal charge transport in 1T‐CrTe2/FeTe heterostructures provides a promising platform for exploring the magnetically controllable superconducting diode effect.
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- Award ID(s):
- 2011839
- PAR ID:
- 10683388
- Publisher / Repository:
- Wiley Advanced
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 38
- Issue:
- 14
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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