Aperiodic quantum oscillations in the two-dimensional electron gas at the LaAlO3/SrTiO3 interface
Source abstract
Abstract
Abstract Despite several attempts, the intimate electronic structure of two-dimensional electron systems buried at the interface between LaAlO3 and SrTiO3 still remains to be experimentally revealed. Here, we investigate the transport properties of a high-mobility quasi-two-dimensional electron gas at this interface under high magnetic field (55 T) and provide new insights for electronic band structure by analyzing the Shubnikov-de Haas oscillations. Interestingly, the quantum oscillations are not 1∕B-periodic and produce a highly non-linear Landau plot (Landau level index versus 1/B). We explore different scenarios leading to 1/B-aperiodic oscillations where the charge and the chemical potential vary as the magnetic field increases. Overall, the magneto-transport data are discussed in light of high-resolution scanning transmission electron microscopy (HRSTEM) analysis of the interface as well as calculations from density functional theory.
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Research context
OpenAlex topics: Electronic and Structural Properties of Oxides · Quantum and electron transport phenomena · Organic and Molecular Conductors Research
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References (42)
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1. Ohtomo, A. & Hwang, H. A high-mobility electron gas at the LaAlO3/SrTiO3 heterointerface. Nature 427, 423–426 (2004).10.1038/nature02308 ↗
2. Reyren, N. et al. Superconducting interfaces between insulating oxides. Science 317, 1196–1199 (2007).10.1126/science.1146006 ↗
3. Li, L., Richter, C., Mannhart, J. & Ashoori, R. C. Coexistence of magnetic order and two-dimensional superconductivity at LaAlO3/SrTiO3 interfaces. Nat. Phys. 7, 762–766 (2011).10.1038/nphys2080 ↗
4. Stornaiuolo, D. et al. Signatures of unconventional superconductivity in the LaAlO3/SrTiO3 two-dimensional system. Phys. Rev. B 95, 140502 (2017).10.1103/PhysRevB.95.140502 ↗
5. Ben Shalom, M., Sachs, M., Rakhmilevitch, D., Palevski, A. & Dagan, Y. Tuning spin-orbit coupling and superconductivity at the LaAlO3/SrTiO3 interface: a magnetotransport study. Phys. Rev. Lett. 104, 126802 (2010).10.1103/PhysRevLett.104.126802 ↗
6. Zhong, Z., Tòth, A. & Held, K. Theory of spin-orbit coupling at LaAlO3/SrTiO3 interfaces and SrTiO3 surfaces. Phys. Rev. B 87, 161102 (2013).10.1103/PhysRevB.87.161102 ↗
7. Caviglia, A. D. et al. Tunable rashba spin-orbit interaction at oxide interfaces. Phys. Rev. Lett. 104, 126803 (2010).10.1103/PhysRevLett.104.126803 ↗
8. Brinkman, A. et al. Magnetic effects at the interface between non-magnetic oxides. Nat. Mater. 6, 493–496 (2007).10.1038/nmat1931 ↗
9. Bert, J. A. et al. Direct imaging of the coexistence of ferromagnetism and superconductivity at the LaAlO3/SrTiO3 interface. Nat. Phys. 7, 767–771 (2011).10.1038/nphys2079 ↗
10. Ariando, A. et al. Electronic phase separation at the LaAlO3/SrTiO3 interface. Nat. Commun. 2, 188 (2011).10.1038/ncomms1192 ↗
11. Caviglia, A. D. et al. Two-dimensional quantum oscillations of the conductance at LaAlO3/SrTiO3 interfaces. Phys. Rev. Lett. 105, 236802 (2010).10.1103/PhysRevLett.105.236802 ↗
12. Ben Shalom, M., Ron, A., Palevski, A. & Dagan, Y. Shubnikov-de haas oscillations in SrTiO3/LaAlO3 interface. Phys. Rev. Lett. 105, 206401 (2010).10.1103/PhysRevLett.105.206401 ↗
13. McCollam, A. et al. Quantum oscillations and subband properties of the two-dimensional electron gas at the LaAlO3/SrTiO3 interface. APL Mater. 2, 022102 (2014).10.1063/1.4863786 ↗
14. Yang, M. et al. High field magneto-transport in two-dimensional electron gas LaAlO3/SrTiO3. Appl. Phys. Lett. 109, 122106 (2016).10.1063/1.4963234 ↗
15. Salluzzo, M. et al. Orbital reconstruction and the two-dimensional electron gas at the LaAlO3/SrTiO3 interface. Phys. Rev. Lett. 102, 166804 (2009).10.1103/PhysRevLett.102.166804 ↗
16. Reinle-Schmitt, M. et al. Tunable conductivity threshold at polar oxide interfaces. Nat. Commun. 3, 932 (2012).10.1038/ncomms1936 ↗
17. Kalabukhov, A. et al. Effect of oxygen vacancies in the SrTiO3 substrate on the electrical properties of the LaAlO3/SrTiO3 interface. Phys. Rev. B 75, 121404 (2007).10.1103/PhysRevB.75.121404 ↗
18. Herranz, G. et al. High mobility in LaAlO3/SrTiO3 heterostructures: origin, dimensionality, and perspectives. Phys. Rev. Lett. 98, 216803 (2007).10.1103/PhysRevLett.98.216803 ↗
19. Fongkaew, I., Limpijumnong, S. & Lambrecht, W. R. L. Effects of structural relaxation, interdiffusion, and surface termination on two-dimensional electron gas formation at the LaAlO3/SrTiO3 (001) interface. Phys. Rev. B 92, 155416 (2015).10.1103/PhysRevB.92.155416 ↗
20. Delugas, P. et al. Spontaneous 2-dimensional carrier confinement at the LaAlO3/SrTiO3 interface. Phys. Rev. Lett. 106, 166807 (2011).10.1103/PhysRevLett.106.166807 ↗
21. van Heeringen, L. W., de Wijs, G. A., McCollam, A., Maan, J. C. & Fasolino, A. kp subband structure of the LaAlO3/SrTiO3 interface. Phys. Rev. B 88, 205140 (2013).10.1103/PhysRevB.88.205140 ↗
22. Fête, A. et al. Large modulation of the shubnikov-de haas oscillations by the rashba interaction at the LaAlO3/SrTiO3 interface. New J. Phys. 16, 112002 (2014).10.1088/1367-2630/16/11/112002 ↗
23. Neville, R. C., Hoeneisen, B. & Mead, C. A. Permittivity of strontium titanate. J. Appl. Phys. 43, 2124–2131 (1972).10.1063/1.1661463 ↗
24. Kalisky, B. et al. Locally enhanced conductivity due to the tetragonal domain structure in LaAlO3/SrTiO3 heterointerfaces. Nat. Mater. 12, 1091–1095 (2013).10.1038/nmat3753 ↗
25. Aurino, P. et al. Retention of electronic conductivity in LaAlO3/SrTiO3 nanostructures using a SrCuO2 capping layer. Phys. Rev. Appl. 6, 024011 (2016).10.1103/PhysRevApplied.6.024011 ↗
26. Yu, L. & Zunger, A. A polarity-induced defect mechanism for conductivity and magnetism at polar-nonpolar oxide interfaces. Nat. Commun. 5, 5118 (2014).10.1038/ncomms6118 ↗
27. Biscaras, J. et al. Limit of the electrostatic doping in two-dimensional electron gases of LaXO3 (X = Al, Ti)/SrTiO3. Sci. Rep. 4, 6788 (2014).10.1038/srep06788 ↗
28. Trier, F. et al. Quantization of Hall resistance at the metallic interface between an oxide insulator and SrTiO3. Phys. Rev. Lett. 117, 096804 (2016).10.1103/PhysRevLett.117.096804 ↗
29. Jalan, B., Stemmer, S., Mack, S. & Allen, S. J. Two-dimensional electron gas in δ -doped SrTiO3. Phys. Rev.B 82, 081103 (2010).10.1103/PhysRevB.82.081103 ↗
30. Cheng, G. et al. Shubnikov de Haas like quantum oscillations in artificial one-dimensional LaAlO3/SrTiO3 electron channels. Phys. Rev. Lett. 120, 076801 (2018).10.1103/PhysRevLett.120.076801 ↗
31. Beenakker, C. & van Houten, H. Quantum transport in semiconductor nanostructures. In Semiconductor Heterostructures and Nanostructures, vol. 44 of Solid State Physics (eds Ehrenreich, H. & Turnbull, D.) 1–228 (Academic Press, 1991).10.1016/S0081-1947(08)60091-0 ↗
32. Argyres, P. N. & Adams, E. N. Longitudinal magnetoresistance in the quantum limit. Phys. Rev. 104, 900–908 (1956).10.1103/PhysRev.104.900 ↗
33. Janssen, T. J. B. M. et al. Anomalously strong pinning of the filling factor ν = 2 in epitaxial graphene. Phys. Rev. B 83, 233402 (2011).10.1103/PhysRevB.83.233402 ↗
34. Yang, M. et al. Puddle-induced resistance oscillations in the breakdown of the graphene quantum hall effect. Phys. Rev. Lett. 117, 237702 (2016).10.1103/PhysRevLett.117.237702 ↗
35. Gao, Y. & Niu, Q. Zero-field magnetic response functions in landau levels. Proc. Natl Acad. Sci. USA 114, 7295–7300 (2017).10.1073/pnas.1702595114 ↗
36. Fuchs, J. N., Piéchon, F. & Montambaux, G. Landau levels, response functions and magnetic oscillations from a generalized onsager relation. SciPost Phys. 4, 024 (2018).10.21468/SciPostPhys.4.5.024 ↗
37. Lee, J.-S. et al. Titanium dxy ferromagnetism at the LaAlO3/SrTiO3 interface. Nat. Mater. 12, 703–706 (2013).10.1038/nmat3674 ↗
38. Fischer, M. H., Raghu, S. & Kim, E.-A. Spin–orbit coupling in LaAlO3/SrTiO3 interfaces: magnetism and orbital ordering. New J. Phys. 15, 023022 (2013).10.1088/1367-2630/15/2/023022 ↗
39. Taskin, A. A. & Ando, Y. Berry phase of nonideal dirac fermions in topological insulators. Phys. Rev. B 84, 035301 (2011).10.1103/PhysRevB.84.035301 ↗
40. Kresse, G. & Hafner, J. Ab initio molecular-dynamics simulation of the liquid-metal-amorphous-semiconductor transition in germanium. Phys. Rev. B 49, 14251–14269 (1994).10.1103/PhysRevB.49.14251 ↗
41. Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).10.1103/PhysRevB.54.11169 ↗
42. Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).10.1103/PhysRevLett.77.3865 ↗