Electronic band structure of superconducting KTaO3 (111) interfaces
Source abstract
Abstract
Two-dimensional electron gases (2DEGs) based on KTaO3 are emerging as a promising platform for spin-orbitronics due to their high Rashba spin–orbit coupling (SOC) and gate-voltage tunability. The recent discovery of a superconducting state in KTaO3 2DEGs now expands their potential towards topological superconductivity. Although the band structure of KTaO3 surfaces of various crystallographic orientations has already been mapped using angle-resolved photoemission spectroscopy (ARPES), this is not the case for superconducting KTaO3 2DEGs. Here, we reveal the electronic structure of superconducting 2DEGs based on KTaO3 (111) single crystals through ARPES measurements. We fit the data with a tight-binding model and compute the associated spin textures to bring insight into the SOC-driven physics of this fascinating system.
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Research context
OpenAlex topics: Electronic and Structural Properties of Oxides · Magnetic and transport properties of perovskites and related materials · Advanced Condensed Matter Physics
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay 1 , 91767 Palaiseau, France
Institut für Physik, Martin-Luther-Universität Halle-Wittenberg 2 , 06099 Halle, Germany
Laboratoire de Physique et d’Etude des Matériaux, ESPCI Paris, Université PSL, CNRS 3 , 75005 Paris, France
Institut des Sciences Moléculaires d’Orsay, CNRS, Université Paris-Saclay 4 , 91405 Orsay, France
SOLEIL Synchrotron 5 , L’Orme des Merisiers, Départementale 128, F-91190 Saint-Aubin, France
Max Planck Institute of Microstructure Physics 6 , Weinberg 2, 06120 Halle, Germany
Funding
Agence Nationale de la Recherche · European Research Council · Deutsche Forschungsgemeinschaft
References (49)
Show source-provided references
1. Emergent phenomena at oxide interfaces10.1038/nmat3223 ↗
2. Oxide spin–orbitronics: Spin–charge interconversion and topological spin textures10.1038/s41578-021-00395-9 ↗
3. A high-mobility electron gas at the LaAlO3/SrTiO3 heterointerface10.1038/nature02308 ↗
4. Universal fabrication of 2D electron systems in functional oxides10.1002/adma.201505021 ↗
5. Metal/SrTiO3 two-dimensional electron gases for spin-to-charge conversion10.1103/physrevmaterials.5.064005 ↗
6. Non-volatile electric control of spin–orbit torques in an oxide two-dimensional electron gas10.1038/s41467-023-37866-2 ↗
7. Electronic transport in strontium titanate10.1103/physrev.134.a442 ↗
8. Superconductivity in semiconducting SrTiO310.1103/physrevlett.12.474 ↗
9. A high-mobility two-dimensional electron gas at the spinel/perovskite interface of γ-Al2O3/SrTiO310.1038/ncomms2394 ↗
10. Superconducting interfaces between insulating oxides10.1126/science.1146006 ↗
11. Electric field control of the LaAlO3/SrTiO3 interface ground state10.1038/nature07576 ↗
12. Tunable Rashba spin–orbit interaction at oxide interfaces10.1103/physrevlett.104.126803 ↗
13. Quantization of Hall resistance at the metallic interface between an oxide insulator and SrTiO310.1103/physrevlett.117.096804 ↗
14. Two-dimensional electron gas with universal subbands at the surface of SrTiO310.1038/nature09720 ↗
15. Direct k-space mapping of the electronic structure in an oxide–oxide interface10.1103/physrevlett.110.247601 ↗
16. Absence of giant spin splitting in the two-dimensional electron liquid at the surface of SrTiO3 (001)10.1103/physrevb.93.245143 ↗
17. Determining the Rashba parameter from the bilinear magnetoresistance response in a two-dimensional electron gas10.1103/physrevmaterials.4.071001 ↗
18. Energy bands for KNiF3, SrTiO3, KMoO3, and KTaO310.1103/PhysRevB.6.4718 ↗
19. Highly efficient and tunable spin-to-charge conversion through Rashba coupling at oxide interfaces10.1038/nmat4726 ↗
20. Efficient spin-to-charge conversion in the 2D electron liquid at the LAO/STO interface10.1209/0295-5075/116/17006 ↗
21. Mapping spin–charge conversion to the band structure in a topological oxide two-dimensional electron gas10.1038/s41563-019-0467-4 ↗
22. Efficient intrinsic spin-to-charge current conversion in an all-epitaxial single-crystal perovskite-oxide heterostructure of La0.67Sr0.33MnO3/LaAlO3/SrTiO310.1103/physrevresearch.2.012014 ↗
23. Orientational tuning of the Fermi sea of confined electrons at the SrTiO3 (110) and (111) surfaces10.1103/physrevapplied.1.051002 ↗
24. Control of a two-dimensional electron gas on SrTiO3 (111) by atomic oxygen10.1103/physrevlett.113.177601 ↗
25. Gap suppression at a Lifshitz transition in a multi-condensate superconductor10.1038/s41563-019-0354-z ↗
26. Multiband effects in the superconducting phase diagram of oxide interfaces10.1002/admi.202201392 ↗
27. Some transport properties of oxygen-deficient single-crystal potassium tantalate (KTaO3)10.1103/physrev.137.a1575 ↗
28. Subband structure of a two-dimensional electron gas formed at the polar surface of the strong spin–orbit perovskite KTaO310.1103/physrevlett.108.117602 ↗
29. Orbital symmetry reconstruction and strong mass renormalization in the two-dimensional electron gas at the surface of KTaO310.1103/physrevb.86.121107 ↗
30. LaTiO3/KTaO3 interfaces: A new two-dimensional electron gas system10.1063/1.4914310 ↗
31. KTaO3—The new kid on the spintronics block10.1002/adma.202106481 ↗
32. Discovery of superconductivity in KTaO3 by electrostatic carrier doping10.1038/nnano.2011.78 ↗
33. Very low-temperature search for superconductivity in semiconducting KTaO310.1007/bf00683987 ↗
34. Spin–charge interconversion in KTaO3 2D electron gases10.1002/adma.202102102 ↗
35. Direct visualization of Rashba-split bands and spin/orbital-charge interconversion at KTaO3 interfaces10.1038/s41467-022-33621-1 ↗
36. Two-dimensional superconductivity and anisotropic transport at KTaO3 (111) interfaces10.1126/science.aba5511 ↗
37. Superfluid stiffness of a KTaO3-based two-dimensional electron gas10.1038/s41467-022-32242-y ↗
38. Anisotropic superconductivity at KTaO3 (111) interfaces10.1126/sciadv.adf1414 ↗
39. Gate tunability of the superconducting state at the EuO/KTaO3 (111) interface10.1103/physrevb.104.184505 ↗
40. Tunable two-dimensional superconductivity and spin–orbit coupling at the EuO/KTaO3(110) interface10.1038/s41535-022-00506-x ↗
41. Theory of superconductivity mediated by Rashba coupling in incipient ferroelectrics10.1103/physrevb.105.224503 ↗
42. Tunable superconductivity and its origin at KTaO3 interfaces10.1038/s41467-023-36309-2 ↗
43. First-principles calculation of electron–phonon coupling in doped KTaO3
44. Two-dimensional electron gas with six-fold symmetry at the (111) surface of KTaO310.1038/srep03586 ↗
45. Band structure and spin–orbital texture of the (111)-KTaO3 2D electron gas10.1002/aelm.201800860 ↗
46. Anisotropic electronic structure of the 2D electron gas at the AlOx/KTaO3(110) interface10.1002/aelm.202300267 ↗
47. X. Chen , T.Yu, Y.Liu, Y.Sun, M.Lei, N.Guo, Y.Fan, X.Sun, M.Zhang, F.Alarab, V. N.Strokov, Y.Wang, T.Zhou, X.Liu, F.Lu, W.Liu, Y.Xie, R.Peng, H.Xu, and D.Feng, “Orientation-dependent electron–phonon coupling in interfacial superconductors LaAlO3/KTaO3,” arXiv:2301.13488 [cond-mat.supr-con] (2023).10.1038/s41467-024-51969-4 ↗
48. Quasiparticle dynamics and spin–orbital texture of the SrTiO3 two-dimensional electron gas10.1038/ncomms4414 ↗
49. Link between the superconducting dome and spin–orbit interaction in the (111) LaAlO3/SrTiO3 interface10.1103/physrevlett.119.237002 ↗