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  • Technical Review
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Opportunities in topological insulator devices

Abstract

Topological insulators (TIs) hold promise as a platform for unique quantum phenomena. However, realizing these phenomena experimentally requires sophisticated devices. In this Technical Review, we discuss four topics of particular interest for TI devices: topological superconductivity, quantum anomalous Hall insulators as a platform for exotic phenomena, spintronic functionalities and topological mesoscopic physics. We also discuss the status and technical challenges in fabricating TI devices to address new physics.

Key points

  • Interesting quantum phenomena deriving from the peculiar properties of topological insulators (TIs) can be observed in TI devices. Fabrication of such devices should take into account the special challenges these materials pose for fabrication.

  • In proximity to a conventional superconductor, TIs can realize a topological superconducting state hosting Majorana zero modes, representing the main ingredient for topological quantum computing, in which TIs can potentially have an advantage over semiconductor platforms.

  • By magnetically doping a TI, the quantum anomalous Hall effect can be observed if the Fermi level is tuned into the magnetic exchange gap and chiral edge states arise that are expected to turn into chiral Majorana edge states if superconductivity is induced by the proximity effect.

  • The spin-momentum-locked surface states of a TI are potentially useful for spintronic applications due to their current-induced spin polarization that interacts with ferromagnetic electrodes.

  • Quantum confinement in mesoscopic-sized TI nanowires leads to the formation of a peculiar Dirac subband structure, which can be modified by magnetic and electric fields to open extended topological phases within which Majorana zero modes are expected if proximitized by a superconductor.

  • Fabricating devices based on TIs and interfacing them with ferromagnets or superconductors requires well-tuned processes in order to preserve and control the surface state properties.

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Fig. 1: TI device fabrication.
Fig. 2: TI/superconductor devices.
Fig. 3: Topological insulator nanowire devices.

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References

  1. Ando, Y. Topological insulator materials. J. Phys. Soc. Jpn. 82, 102001 (2013).

    Article  ADS  Google Scholar 

  2. He, Q. L. et al. Chiral Majorana fermion modes in a quantum anomalous Hall insulator–superconductor structure. Science 357, 294–299 (2017).

    Article  MathSciNet  MATH  ADS  Google Scholar 

  3. Kayyalha, M. et al. Absence of evidence for chiral Majorana modes in quantum anomalous Hall-superconductor devices. Science 367, 64–67 (2020).

    Article  ADS  Google Scholar 

  4. Aguado, R. & Kouwenhoven, L. P. Majorana qubits for topological quantum computing. Phys. Today 73, 44–50 (2020).

    Article  Google Scholar 

  5. Manousakis, J., Altland, A., Bagrets, D., Egger, R. & Ando, Y. Majorana qubits in a topological insulator nanoribbon architecture. Phys. Rev. B 95, 165424 (2017).

    Article  ADS  Google Scholar 

  6. Qi, X.-L., Hughes, T. L. & Zhang, S.-C. Topological field theory of time-reversal invariant insulators. Phys. Rev. B 78, 195424 (2008).

    Article  ADS  Google Scholar 

  7. Mogi, M. et al. A magnetic heterostructure of topological insulators as a candidate for an axion insulator. Nat. Mater. 16, 516–521 (2017).

    Article  ADS  Google Scholar 

  8. Xiao, D. et al. Realization of the axion insulator state in quantum anomalous Hall sandwich heterostructures. Phys. Rev. Lett. 120, 056801 (2018).

    Article  ADS  Google Scholar 

  9. Münning, F. et al. Quantum confinement of the Dirac surface states in topological-insulator nanowires. Nat. Commun. 12, 1038 (2021).

    Article  ADS  Google Scholar 

  10. Cho, S. et al. Aharonov–Bohm oscillations in a quasi-ballistic three-dimensional topological insulator nanowire. Nat. Commun. 6, 7634 (2015).

    Article  ADS  Google Scholar 

  11. Wiedenmann, J. et al. 4π-periodic Josephson supercurrent in HgTe-based topological Josephson junctions. Nat. Commun. 7, 10303 (2016).

    Article  ADS  Google Scholar 

  12. Deacon, R. S. et al. Josephson radiation from gapless Andreev bound states in HgTe-based topological junctions. Phys. Rev. X 7, 021011 (2017).

    Google Scholar 

  13. Taskin, A. A. et al. Planar Hall effect from the surface of topological insulators. Nat. Commun. 8, 1340 (2017).

    Article  ADS  Google Scholar 

  14. Yasuda, K. et al. Quantized chiral edge conduction on domain walls of a magnetic topological insulator. Science 358, 1311–1314 (2017).

    Article  ADS  Google Scholar 

  15. Chen, A. Q. et al. Finite momentum Cooper pairing in three-dimensional topological insulator Josephson junctions. Nat. Commun. 9, 3478 (2018).

    Article  ADS  Google Scholar 

  16. Schüffelgen, P. et al. Selective area growth and stencil lithography for in situ fabricated quantum devices. Nat. Nanotechnol. 14, 825–831 (2019).

    Article  ADS  Google Scholar 

  17. Sato, M. & Ando, Y. Topological superconductors: a review. Rep. Prog. Phys. 80, 076501 (2017).

    Article  MathSciNet  ADS  Google Scholar 

  18. Mackenzie, A. P., Scaffidi, T., Hicks, C. W. & Maeno, Y. Even odder after twenty-three years: the superconducting order parameter puzzle of Sr2RuO4. NPJ Quantum Mater. 2, 40 (2017).

    Article  ADS  Google Scholar 

  19. Alicea, J. New directions in the pursuit of Majorana fermions in solid state systems. Rep. Prog. Phys. 75, 076501 (2012).

    Article  ADS  Google Scholar 

  20. Aasen, D. et al. Milestones toward Majorana-based quantum computing. Phys. Rev. X 6, 031016 (2016).

    Google Scholar 

  21. Nayak, C., Stern, A., Freedman, M. & Das Sarma, S. Non-Abelian anyons and topological quantum computation. Rev. Mod. Phys. 80, 1083–1159 (2008).

    Article  MathSciNet  MATH  ADS  Google Scholar 

  22. Fu, L. & Kane, C. L. Superconducting proximity effect and Majorana fermions at the surface of a topological insulator. Phys. Rev. Lett. 100, 096407 (2008).

    Article  ADS  Google Scholar 

  23. Williams, J. R. et al. Unconventional Josephson effect in hybrid superconductor-topological insulator devices. Phys. Rev. Lett. 109, 056803 (2012).

    Article  ADS  Google Scholar 

  24. Oostinga, J. B. et al. Josephson supercurrent through the topological surface states of strained bulk HgTe. Phys. Rev. X 3, 021007 (2013).

    Google Scholar 

  25. Ghatak, S. et al. Anomalous Fraunhofer patterns in gated Josephson junctions based on the bulk-insulating topological insulator BiSbTeSe2. Nano Lett. 18, 5124–5131 (2018).

    Article  ADS  Google Scholar 

  26. Bocquillon, E. et al. Gapless Andreev bound states in the quantum spin Hall insulator HgTe. Nat. Nanotechnol. 12, 137–143 (2017).

    Article  ADS  Google Scholar 

  27. Li, C. et al. 4π-periodic Andreev bound states in a Dirac semimetal. Nat. Mater. 17, 875–880 (2018).

    Article  ADS  Google Scholar 

  28. Dartiailh, M. C. et al. Missing Shapiro steps in topologically trivial Josephson junction on InAs quantum well. Nat. Commun. 12, 78 (2021).

    Article  ADS  Google Scholar 

  29. Prada, E. et al. From Andreev to Majorana bound states in hybrid superconductor–semiconductor nanowires. Nat. Rev. Phys. 2, 575–594 (2020).

    Article  Google Scholar 

  30. Woods, B. D., Das Sarma, S. & Stanescu, T. D. Charge impurity effects in hybrid Majorana nanowires. Preprint at arXiv https://arxiv.org/abs/2103.06880 (2021).

  31. Legg, H. F., Loss, D. & Klinovaja, J. Majorana bound states in topological insulators without a vortex. Phys. Rev. B 104, 165405 (2021).

    Article  ADS  Google Scholar 

  32. Huang, Y. & Shklovskii, B. I. Disorder effects in topological insulator nanowires. Phys. Rev. B 104, 054205 (2021).

    Article  ADS  Google Scholar 

  33. Chang, C.-Z. et al. Experimental observation of the quantum anomalous Hall effect in a magnetic topological insulator. Science 340, 167–170 (2013).

    Article  ADS  Google Scholar 

  34. Chang, C.-Z. et al. High-precision realization of robust quantum anomalous Hall state in a hard ferromagnetic topological insulator. Nat. Mater. 14, 473–477 (2015).

    Article  ADS  Google Scholar 

  35. Deng, Y. et al. Quantum anomalous Hall effect in intrinsic magnetic topological insulator MnBi2Te4. Science 367, 895–900 (2020).

    Article  ADS  Google Scholar 

  36. Kawamura, M. et al. Current-driven instability of the quantum anomalous Hall effect in ferromagnetic topological insulators. Phys. Rev. Lett. 119, 016803 (2017).

    Article  ADS  Google Scholar 

  37. Lippertz, G. et al. Current-induced breakdown of the quantum anomalous Hall effect. Preprint at arXiv https://arxiv.org/abs/2108.02081 (2021).

  38. Yasuda, K. et al. Large non-reciprocal charge transport mediated by quantum anomalous Hall edge states. Nat. Nanotechnol. 15, 831–835 (2020).

    Article  ADS  Google Scholar 

  39. Qi, X.-L., Hughes, T. L. & Zhang, S.-C. Chiral topological superconductor from the quantum Hall state. Phys. Rev. B 82, 184516 (2010).

    Article  ADS  Google Scholar 

  40. Wilczek, F. Majorana returns. Nat. Phys. 5, 614–618 (2009).

    Article  Google Scholar 

  41. Beenakker, C. W. J. et al. Deterministic creation and braiding of chiral edge vortices. Phys. Rev. Lett. 122, 146803 (2019).

    Article  ADS  Google Scholar 

  42. Hassler, F. et al. Half-integer charge injection by a Josephson junction without excess noise. Phys. Rev. B 102, 045431 (2020).

    Article  ADS  Google Scholar 

  43. Zeng, Y., Lei, C., Chaudhary, G. & MacDonald, A. H. Quantum anomalous Hall Majorana platform. Phys. Rev. B 97, 081102 (2018).

    Article  ADS  Google Scholar 

  44. Fu, L. Hexagonal warping effects in the surface states of the topological insulator Bi2Te3. Phys. Rev. Lett. 103, 266801 (2009).

    Article  ADS  Google Scholar 

  45. Hellman, F. et al. Interface-induced phenomena in magnetism. Rev. Mod. Phys. 89, 025006 (2017).

    Article  MathSciNet  ADS  Google Scholar 

  46. Yang, F. et al. Switching of charge-current-induced spin polarization in the topological insulator BiSbTeSe2. Phys. Rev. B 94, 075304 (2016).

    Article  ADS  Google Scholar 

  47. Li, C. H. et al. Electrical detection of charge-current-induced spin polarization due to spin-momentum locking in Bi2Se3. Nat. Nanotechnol. 9, 218–224 (2014).

    Article  ADS  Google Scholar 

  48. Zhang, Y. & Vishwanath, A. Anomalous Aharonov-Bohm conductance oscillations from topological insulator surface states. Phys. Rev. Lett. 105, 206601 (2010).

    Article  ADS  Google Scholar 

  49. Bardarson, J. H., Brouwer, P. W. & Moore, J. E. Aharonov-Bohm oscillations in disordered topological insulator nanowires. Phys. Rev. Lett. 105, 156803 (2010).

    Article  ADS  Google Scholar 

  50. Cook, A. & Franz, M. Majorana fermions in a topological-insulator nanowire proximity-coupled to an s-wave superconductor. Phys. Rev. B 84, 201105 (2011).

    Article  ADS  Google Scholar 

  51. Peng, H. et al. Aharonov–Bohm interference in topological insulator nanoribbons. Nat. Mater. 9, 225–229 (2010).

    Article  ADS  Google Scholar 

  52. Jauregui, L. A., Pettes, M. T., Rokhinson, L. P., Shi, L. & Chen, Y. P. Magnetic field-induced helical mode and topological transitions in a topological insulator nanoribbon. Nat. Nanotechnol. 11, 345–351 (2016).

    Article  ADS  Google Scholar 

  53. Legg, H. F. et al. Giant magnetochiral anisotropy from quantum confined surface states of topological insulator nanowires. Preprint at arXiv https://arxiv.org/abs/2109.05188 (2021).

  54. Zhang, J. et al. Band structure engineering in (Bi1−xSbx)2Te3 ternary topological insulators. Nat. Commun. 2, 574 (2011).

    Article  ADS  Google Scholar 

  55. Ren, Z., Taskin, A. A., Sasaki, S., Segawa, K. & Ando, Y. Optimizing Bi2−xSbxTe3−ySey solid solutions to approach the intrinsic topological insulator regime. Phys. Rev. B 84, 165311 (2011).

    Article  ADS  Google Scholar 

  56. Yang, F. et al. Top gating of epitaxial (Bi1−xSbx)2Te3 topological insulator thin films. Appl. Phys. Lett. 104, 161614 (2014).

    Article  ADS  Google Scholar 

  57. Volykhov, A. A. et al. Rapid surface oxidation of Sb2Te3 as indication for a universal trend in the chemical reactivity of tetradymite topological insulators. Chem. Mater. 28, 8916–8923 (2016).

    Article  Google Scholar 

  58. Volykhov, A. A. et al. Can surface reactivity of mixed crystals be predicted from their counterparts? A case study of (Bi1−xSbx)2Te3 topological insulators. J. Mater. Chem. C 6, 8941–8949 (2018).

    Article  Google Scholar 

  59. Taskin, A. A., Ren, Z., Sasaki, S., Segawa, K. & Ando, Y. Observation of Dirac holes and electrons in a topological insulator. Phys. Rev. Lett. 107, 016801 (2011).

    Article  ADS  Google Scholar 

  60. Hoefer, K., Becker, C., Wirth, S. & Hao Tjeng, L. Protective capping of topological surface states of intrinsically insulating Bi2Te3. AIP Adv. 5, 097139 (2015).

    Article  ADS  Google Scholar 

  61. Steinberg, H., Laloë, J.-B., Fatemi, V., Moodera, J. S. & Jarillo-Herrero, P. Electrically tunable surface-to-bulk coherent coupling in topological insulator thin films. Phys. Rev. B 84, 233101 (2011).

    Article  ADS  Google Scholar 

  62. Schüffelgen, P. et al. Stencil lithography of superconducting contacts on MBE-grown topological insulator thin films. J. Cryst. Growth 477, 183–187 (2017).

    Article  ADS  Google Scholar 

  63. Yang, F. et al. Dual-gated topological insulator thin-film device for efficient Fermi-level tuning. ACS Nano 9, 4050–4055 (2015).

    Article  Google Scholar 

  64. Wang, J. et al. Two-dimensional-Dirac surface states and bulk gap probed via quantum capacitance in a three-dimensional topological insulator. Nano Lett. 20, 8493–8499 (2020).

    Article  ADS  Google Scholar 

  65. Checkelsky, J. G. et al. Trajectory of the anomalous Hall effect towards the quantized state in a ferromagnetic topological insulator. Nat. Phys. 10, 731–736 (2014).

    Article  Google Scholar 

  66. Fatemi, V. et al. Electrostatic coupling between two surfaces of a topological insulator nanodevice. Phys. Rev. Lett. 113, 206801 (2014).

    Article  ADS  Google Scholar 

  67. Gazibegovic, S. et al. Epitaxy of advanced nanowire quantum devices. Nature 548, 434–438 (2017).

    Article  ADS  Google Scholar 

  68. Heedt, S. et al. Shadow-wall lithography of ballistic superconductor–semiconductor quantum devices. Nat. Commun. 12, 4914 (2021).

    Article  ADS  Google Scholar 

  69. Wang, Y. H. et al. Observation of chiral currents at the magnetic domain boundary of a topological insulator. Science 349, 948–952 (2015).

    Article  ADS  Google Scholar 

  70. Katmis, F. et al. A high-temperature ferromagnetic topological insulating phase by proximity coupling. Nature 533, 513–516 (2016).

    Article  ADS  Google Scholar 

  71. Watanabe, R. et al. Quantum anomalous Hall effect driven by magnetic proximity coupling in all-telluride based heterostructure. Appl. Phys. Lett. 115, 102403 (2019).

    Article  ADS  Google Scholar 

  72. Fan, Y. et al. Magnetization switching through giant spin–orbit torque in a magnetically doped topological insulator heterostructure. Nat. Mater. 13, 699–704 (2014).

    Article  ADS  Google Scholar 

  73. Khang, N. H. D., Ueda, Y. & Hai, P. N. A conductive topological insulator with large spin Hall effect for ultralow power spin–orbit torque switching. Nat. Mater. 17, 808–813 (2018).

    Article  ADS  Google Scholar 

  74. Xiu, F. et al. Manipulating surface states in topological insulator nanoribbons. Nat. Nanotechnol. 6, 216–221 (2011).

    Article  ADS  Google Scholar 

  75. Rosenbach, D. et al. Quantum transport in topological surface states of selectively grown Bi2Te3 nanoribbons. Adv. Electron. Mater. 6, 2000205 (2020).

    Article  Google Scholar 

  76. Kurter, C., Finck, A. D. K., Ghaemi, P., Hor, Y. S. & Van Harlingen, D. J. Dynamical gate-tunable supercurrents in topological Josephson junctions. Phys. Rev. B 90, 014501 (2014).

    Article  ADS  Google Scholar 

  77. Bai, M. et al. Novel self-epitaxy for inducing superconductivity in the topological insulator (Bi1−xSbx)2Te3. Phys. Rev. Mater. 4, 094801 (2020).

    Article  Google Scholar 

  78. Zhang, D. et al. Superconducting proximity effect and possible evidence for Pearl vortices in a candidate topological insulator. Phys. Rev. B 84, 165120 (2011).

    Article  ADS  Google Scholar 

  79. Bhattacharyya, B., Awana, V. P. S., Senguttuvan, T. D., Ojha, V. N. & Husale, S. Proximity-induced supercurrent through topological insulator based nanowires for quantum computation studies. Sci. Rep. 8, 17237 (2018).

    Article  ADS  Google Scholar 

  80. Yang, F. et al. Proximity-effect-induced superconducting phase in the topological insulator Bi2Se3. Phys. Rev. B 86, 134504 (2012).

    Article  ADS  Google Scholar 

  81. Qu, F. et al. Strong superconducting proximity effect in Pb-Bi2Te3 hybrid structures. Sci. Rep. 2, 339 (2012).

    Article  Google Scholar 

  82. Trang, C. X. et al. Conversion of a conventional superconductor into a topological superconductor by topological proximity effect. Nat. Commun. 11, 159 (2020).

    Article  ADS  Google Scholar 

  83. Octavio, M., Tinkham, M., Blonder, G. E. & Klapwijk, T. M. Subharmonic energy-gap structure in superconducting constrictions. Phys. Rev. B 27, 6739–6746 (1983).

    Article  ADS  Google Scholar 

  84. Xiang, J., Vidan, A., Tinkham, M., Westervelt, R. M. & Lieber, C. M. Ge/Si nanowire mesoscopic Josephson junctions. Nat. Nanotechnol. 1, 208–213 (2006).

    Article  ADS  Google Scholar 

  85. Blonder, G. E., Tinkham, M. & Klapwijk, T. M. Transition from metallic to tunneling regimes in superconducting microconstrictions: excess current, charge imbalance, and supercurrent conversion. Phys. Rev. B 25, 4515–4532 (1982).

    Article  ADS  Google Scholar 

  86. Galaktionov, A. V. & Zaikin, A. D. Quantum interference and supercurrent in multiple-barrier proximity structures. Phys. Rev. B 65, 184507 (2002).

    Article  ADS  Google Scholar 

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Acknowledgements

The authors thank J. Feng, M. Rössler, D. Fan, L. Dang, F. Münning, G. Lippertz and A. Taskin for providing device pictures, and Y. Tokura, M. Kawasaki, H. F. Legg, D. Grützmacher, P. Schüffelgen and F. Yang for useful discussions. This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 741121) and was also funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under CRC 1238-277146847 (subprojects A04 and B01) and AN 1004/4-1-398945897, as well as under Germany’s Excellence Strategy — Cluster of Excellence Matter and Light for Quantum Computing (ML4Q) EXC 2004/1 — 390534769.

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Y.A. conceived the article, with input from O.B. O.B. and Y.A. wrote the manuscript.

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Correspondence to Yoichi Ando.

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Glossary

Chiral Majorana fermions

Fermionic particles that are their own antiparticles, arising as a 1D gapless edge mode, as expected in a proximitized quantum anomalous Hall insulator.

Topological qubits

A quantum system incorporating Majorana zero modes that allows quantum computation based on non-abelian exchange statistics to enable ‘digital’-like gate operation, as opposed to ‘analogue’-like conventional qubits.

Majorana zero modes

(MZMs). Localized bound states having a self-conjugate property, which can be viewed as an emergent Majorana particle obeying non-abelian exchange statistics.

Superconducting proximity effect

The extension of Cooper pairing from a superconductor into a normal system that is in close proximity.

Shapiro step

A step in the current–voltage characteristics of a Josephson junction upon microwave irradiation, caused by the AC Josephson effect.

Rashba-type band splitting

Splitting of a spin-degenerate band into a pair of spin-non-degenerate bands having opposite helical spin polarization.

Zeeman energy gap

An energy gap that is induced by the action of a magnetic field on the spin magnetic moment.

London penetration depth

The characteristic length over which a magnetic field penetrates into a superconductor.

Fraunhofer pattern

The magnetic field dependence of the critical current of a Josephson junction obeying the same pattern as the Fraunhofer diffraction.

Hexagonal warping

Deviation from the ideal circular Fermi surface of the Dirac cone caused by third-order spin–orbit coupling.

Size quantization

Discretization of the quantum-mechanical eigenenergies due to spatial confinement.

Kramers degeneracy

The ever-present double degeneracy of eigenstates of a fermionic system that is time-reversal invariant.

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Breunig, O., Ando, Y. Opportunities in topological insulator devices. Nat Rev Phys 4, 184–193 (2022). https://doi.org/10.1038/s42254-021-00402-6

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