Topological nodal-point superconductivity in a 2D-antiferromagnet/superconductor hybrid system
ORAL
Abstract
In the recent years, pioneering studies have been carried out on magnet/superconductor hybrid systems [1-4], motivated by their potential to host emergent quantum phases such as topological superconductivity [5]. So far, the attention has been mainly focused on hybrid systems with a ferromagnetic order [1,3,4,6], which are understood as gapped topological superconductors with a finite Chern number [7,8] defining the amount of end states and propagating edge modes.
Here, we present the discovery of a topological nodal-point superconducting phase in a hybrid system consisting of antiferromagnetic manganese (Mn) monolayer islands on top of the s-wave superconductor niobium (Nb) [9]. The novel topological superconducting phase was discovered via a low-temperature spin-polarized scanning tunneling microscopy and spectroscopy investigation. Low-energy edge modes are observed at the boundaries of the magnetic islands, separating the topological phase from the trivial one. In accordance to tight-binding calculations, we find that the relative spectral weight of the edge modes depends on the edge’s atomic configuration, which is a fingerprint of the discovered topological superconducting state. Our results establish the combination of antiferromagnetism and superconductivity as a novel route to design 2D topological quantum phases.
[1] S. Nadj Perge et al., Science 346, 602-607 (2014).
[2] H. Kim et al., Sci. Adv. 4, eaar5251 (2018).
[3] A. Palacio-Morales et al., Sci. Adv. 5, eaav6600 (2019).
[4] L. Schneider et al., Nat. Phys. 17, 943-948 (2021).
[5] J. Li et al., Nat. Commun. 7:12297 (2016).
[6] S. Kezilebieke et al., Nature 588, 424 (2020).
[7] A. P. Schnyder, et al., Phys. Rev. B. 78, 195125 (2008).
[8] C. Chiu, et al. Rev. Mod. Phys., 88, 035005 (2016).
[9] R. Lo Conte et al., Phys. Rev. B 105, L100406 (2022). M. Bazarnik et al., arXiv:2208.12018 (2022).
Here, we present the discovery of a topological nodal-point superconducting phase in a hybrid system consisting of antiferromagnetic manganese (Mn) monolayer islands on top of the s-wave superconductor niobium (Nb) [9]. The novel topological superconducting phase was discovered via a low-temperature spin-polarized scanning tunneling microscopy and spectroscopy investigation. Low-energy edge modes are observed at the boundaries of the magnetic islands, separating the topological phase from the trivial one. In accordance to tight-binding calculations, we find that the relative spectral weight of the edge modes depends on the edge’s atomic configuration, which is a fingerprint of the discovered topological superconducting state. Our results establish the combination of antiferromagnetism and superconductivity as a novel route to design 2D topological quantum phases.
[1] S. Nadj Perge et al., Science 346, 602-607 (2014).
[2] H. Kim et al., Sci. Adv. 4, eaar5251 (2018).
[3] A. Palacio-Morales et al., Sci. Adv. 5, eaav6600 (2019).
[4] L. Schneider et al., Nat. Phys. 17, 943-948 (2021).
[5] J. Li et al., Nat. Commun. 7:12297 (2016).
[6] S. Kezilebieke et al., Nature 588, 424 (2020).
[7] A. P. Schnyder, et al., Phys. Rev. B. 78, 195125 (2008).
[8] C. Chiu, et al. Rev. Mod. Phys., 88, 035005 (2016).
[9] R. Lo Conte et al., Phys. Rev. B 105, L100406 (2022). M. Bazarnik et al., arXiv:2208.12018 (2022).
*EU Marie Curie Fellowship (748006). Deutsche Forschungsgemeinschaft (DFG) Projects No. 459025680, 418425860. Polish Ministry of Education and Science within Project No. 0512/SBAD/2220. EU ERC Advanced Grant ADMIRE (786020). DFG Cluster of Excellence 'Advanced Imaging of Matter' (EXC 2056 - project ID 390715994). Australian Research Council project DP200101118. U. S. DoE, Office of Science, Basic Energy Sciences, Award No. DE-FG02-05ER46225.
–
Publication: R. Lo Conte et al., Phys. Rev. B 105, L100406 (2022).
M. Bazarnik et al., arXiv:2208.12018 (2022).
Presenters
-
Roberto Lo Conte
- University of Hamburg