Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Kondo-like zero-bias conductance anomaly in a three-dimensional topological insulator nanowire


Zero-bias anomalies in topological nanowires have recently captured significant attention, as they are possible signatures of Majorana modes. Yet there are many other possible origins of zero-bias peaks in nanowires—for example, weak localization, Andreev bound states, or the Kondo effect. Here, we discuss observations of differential-conductance peaks at zero-bias voltage in non-superconducting electronic transport through a 3D topological insulator (Bi1.33Sb0.67)Se3 nanowire. The zero-bias conductance peaks show logarithmic temperature dependence and often linear splitting with magnetic fields, both of which are signatures of the Kondo effect in quantum dots. We characterize the zero-bias peaks and discuss their origin.


The three dimensional topological insulator (3D TI) is a new class of material having metallic surface states inside a bulk band gap1,2,3. The topological surface states are characterized by gapless Dirac dispersions and novel properties such as momentum-spin locking, which were confirmed by angle-resolved photoemission spectroscopy (ARPES)4,5,6, scanning tunneling spectroscopy (STS)7,8,9,10,11 and electrical transport measurements12,13,14,15,16,17,18,19. 3D TI nanowires with an insulating bulk, which can be described as a hollow metallic cylinder, have shown Aharonov-Bohm oscillations when a magnetic flux is threaded through the axis20,21 and Coulomb blockade behavior when connected to metal electrodes through ultrathin TI tunnel barriers22. Recently, TI nanowires in the proximity of s-wave superconductors have been predicted to harbor Majorana bound states23,24, a transport signature of which is a zero-bias tunneling-conductance peak. Similar proximity-coupled topological nanowire systems of InSb25 and Fe26 have recently demonstrated Majorana-like zero-bias anomalies, leading to a worldwide effort to better understand the origin and behavior of zero-bias anomalies in topological wires. Zero-bias conductance peaks, not observed yet in 3D TI nanowires, are novel features which may be related to various physical origins such as weak antilocalization, Andreev bound states, and Kondo effect besides Majorana bound states27,28,29. Here we report the first observation of zero-bias anomalies in non-superconducting electronic transport through a 3D TI nanowire contacted by two metal electrodes. We also observed a logarithmic temperature dependence and linear splitting with magnetic fields, both of which imply that the zero-bias peaks result from Kondo-like effect.


We have grown bulk (Bi1.33Sb0.67)Se3 crystals and confirmed the existence of the surface states inside the bulk band gap by ARPES, as described elsewhere30. Using the “scotch tape method”, we obtained naturally cleaved topological insulator nanowires on 300 nm SiO2/highly n-doped Si substrates. Subsequently, we characterized and chose nanowires having widths ≤100 nm and thickness >12 nm by atomic force microscope, to avoid unwanted wavefunction hybridizations of top and bottom surfaces31. Widths of nanowires were measured again, after all the electrical measurements were done, by scanning electron microscopy (SEM). Immediately after we chose nanowires and identified their locations on a SiO2/Si chip, we spun an electron-beam resist (Microchem Corp. PMMA 950 A4) double layer at 4000 rpm to avoid possible contamination or excessive doping of the nanowire surfaces by long exposure to air32. Subsequently, we performed electron beam lithography, developed to remove the resist in the regions of source/drain electrodes, and finally deposited Ti/Al (2.5 nm /150 nm) with an Au 10 nm capping following a brief ion milling at low power. The devices were wire-bonded and cooled-down in a commercial dilution refrigerator immediately following lift-off in acetone for 1 hour. Figure 1(a) is a false-colored SEM image of a completed device, where a small section of the nanowire having dimensions of width ~90 nm, length ~90 nm, and thickness ~13 nm is contacted by a source and a drain electrode.

Figure 1: Device image and characterization.

(a) False-colored Scanning Electron Microscope image of the two-terminal topological insulator nanowire device. (b) Two-probe differential conductance dI/dV as a function of back-gate voltage Vg at B = 50 mT and T = 16 mK at zero bias-voltage. (c,d) Two-dimensional plot of G(Vsd,Vg) and G(Vsd) at Vg = −53.7 V measured at perpendicular magnetic field B = 200 mT.

Here, we report our two-probe differential conductance measurements made between Ti/Al source-drain electrodes driven normal (non-superconducting). To do this, we applied small perpendicular magnetic fields of 30 − 200 mT, which is above the critical field of the Al electrodes ~12 mT (see Supplementary Info.). Figure 1(b) shows that as gate voltage decreased, differential conductance (dI/dV) at zero-bias voltage decreased due to the decrease in the density of states, and finally as gate voltages exceeded Vg = −80 V, the conductance reached its minimum implying that the chemical potential is tuned near the charge neutrality point and therefore a minimum density of states. Due to the low electron doping of our Sb-doped crystals and exfoliated devices as reported previously21,30, we are able to tune the chemical potential effectively below the bottom of the bulk conduction band using a back-gate through SiO2 in our nanowire device. In all range of gate voltages, we observed reproducible conductance fluctuations reminiscent of Coulomb charging effect or phase coherent interference effects such as Fabry-Perot and universal conductance fluctuations.

Figure 1(c) shows differential conductance spectroscopy, a two-dimensional plot of G(Vsd,Vg) measured while varying dc source-drain bias-voltages Vsd at different gate voltages Vg. The transport spectroscopy unexpectedly showed enhanced zero-bias conductance persisting with gate voltages at Vg < −50 V where the background conductance ≤ 5 e2/h. Figure 1(d) shows differential conductance as a function of bias voltages at Vg = −53.7 V. We have further performed differential conductance spectroscopy measurements in wider ranges of gate voltages as shown in Fig. 2. Zero-bias conductance peaks having amplitudes ranging from 0.05 to 0.7 e2/h were observed in a wide range of gate voltages. Often, zero-bias conductance dips appeared in certain regions of gate voltages as shown in Fig. 2(a,c). In the rest of this letter, we discuss the possible origin of the observed zero-bias conductance anomaly.

Figure 2: Differential conductance spectroscopy.

(a,d,f) Two-dimensional plots of G(Vsd,Vg) measured with perpendicular magnetic field B = 200 mT applied in different gate voltage ranges. (b,c,e,g) Differential conductance as a function of bias voltage at fixed gate voltages, (b)−53.3 V, (c)−53.0 V, (e)−74.4 V, and (g)−131.6 V. Each gate voltage whose differential conductance was plotted is marked with yellow dotted-lines in the two-dimensional plots (a,d,f).


Recently, zero-bias peaks observed in 1D topological superconductors, i.e., a strong spin-orbit coupled semiconducting nanowires in the proximity of superconductors under a parallel magnetic field, captured significant attention. The zero-bias anomaly in those systems have been explained as a signature of Majorana zero modes23. There have been similar theoretical proposals on producing Majorana zero modes in topological insulator (Bi2Se3) nanowires proximity-coupled to s-wave superconductors under a parallel magnetic field23,24. However, the absence of superconductivity in a magnetic field higher than the critical field of the Al electrodes in our setup excludes the Majorana zero modes among possible explanations for our zero-bias peaks. Due to the lack of superconductivity, Andreev states bound to superconductors also do not provide an explanation for our observed zero-bias conductance peaks.

To understand the origin of the zero-bias conductance peaks, we have performed the transport measurements at different magnetic fields. Figure 3 shows two different ways in which peaks evolve with magnetic fields at fixed gate voltages (see Supplementary Fig. S4 for 2D G(Vsd,Vg) plot). Peaks having large amplitude (>0.4 e2/h, such as the one) measured at Vg = −69 V, split with magnetic fields (Fig. 3(a,b)). The formation of zero-bias peaks and the splitting of the peaks with a magnetic field are reminiscent of the Kondo effect in quantum dots. A characteristic feature of the Kondo effect in quantum dots is that the zero-bias peak splits with magnetic field at B (the Zeeman splitting), where μB is the Bohr magneton. Assuming the relation of the zero-bias peaks to Kondo effect, we estimate the Zeeman g-factor of the surface states in our topological insulator (Bi1.33Sb0.67)Se3 nanowire is ~15 from the blue line in Fig. 3(b), which is roughly half the reported g factor value of the bulk states in Bi2Se333. On the other hand, peaks of relatively small amplitude (<0.1 e2/h), such as that observed at Vg = −65 V, switched to conductance dips without splitting as the magnetic field was increased (Fig. 3(c)). This collapse of the zero-bias peaks having small peak amplitudes (<0.1 e2/h) with a magnetic field, without being splitted, and having large background conductance is most likely due to lower Kondo temperatures (T ~ TK) at these gate voltages34.

Figure 3: Evolution of zero-bias conductance peaks with magnetic fields.

(a) Differential conductance as a function of bias voltages at a fixed gate Vg = −69 V and different magnetic fields. (b) Two-dimensional plots of (a). Blue lines show splitting of the zero-bias conductance peaks with magnetic fields. (c) Differential conductance as a function of bias voltages at a fixed gate Vg = −65 V and different magnetic fields.

To further investigate the observed Kondo-like anomaly at zero-bias voltage, we measured temperature dependence of the zero-bias peaks. Figure 4 shows that conductance of peaks having both small and large amplitudes increases logarithmically with decreasing temperature and eventually saturated to a constant conductance value as T → 035 (see also Supplementary Fig. S4 for 2D G(Vsd,Vg) plot). In the high-temperature limit, Small peaks with large background conductance vanished at relatively low temperatures <1 K as shown in Fig 4(a), and the large peaks with relatively small conductance background did not vanish up to the temperature limit (~1.8 K) in our dilution refrigerator. Both the logarithmic temperature dependence and the peak splitting with magnetic field suggest that the zero-bias peaks are Kondo-like effects in a quantum dot. We obtain rough estimates of the Kondo temperatures, TK, which ranges from 300 mK to 5 K, by equating the full-width at half-maximum of different zero-bias conductance peaks at the base temperature to 2kBTK/e35,36.

Figure 4: Temperature dependence of zero-bias conductance peaks.

Temperature dependence of zero-bias conductance peaks observed at (a,b) Vg = −60 V, and (c,d) Vg = −72.7 V. Conductance of peaks having both small and large amplitudes decreased logarithmically with temperature.

The Kondo effect describes the upturn of the resistance of metals at low temperatures when magnetic impurities are added37. A similar Kondo effect in semiconducting nanostructures results from a bound state formed between a local spin in a quantum dot and the electrons in the reservoir of source/drain electrodes. We find that the overall background conductance values in our experiments are relatively high (3e2/h < G < 5e2/h) compared to the conductance values (G < 2e2/h) previously reported in quantum dots showing the Kondo effect35,36, and that our topological insulator nanowire device behaves as an open quantum dot. Coulomb charging is required in order for the Kondo effect to be observed in quantum dots; this is usually observed in a system having low dot-electrode transmission probabilities and conductance less than 2e2/h. However, Coulomb charging effects have often been observed in open quantum dots where 2 e2/h < G < 6 e2/h 38,39,40. Therefore, high overall conductance values of 3e2/h < G < 5e2/h does not necessarily exclude the possibility of Coulomb charging and the Kondo effect in our open quantum dot device. The large, oval regions of low-conductance shown in the 2D transport spectroscopy G(Vsd, Vg) of Fig. 2(a) at −54 < Vg < −53, −52 < Vg < −51and −50.5 < Vg < −49.5 are consistent with a diamond-shaped Coulomb blockade in the presence of high lead-dot transparency. Although we do not clearly observe the even-odd parity behavior typical for the Kondo effect in quantum dots, several experiments of Kondo resonances have reported the absence of even-odd parity behavior41,42,43, due to either the formation of higher spin states (spin-triplet Kondo resonances) or correlation effects due to electron-electron interaction dominating over the confinement effect in quantum dots.

We often observe zero-bias peaks that increased with increasing magnetic field (see Supplementary Info.). This has previously been explained by singlet-triplet transitions of electron spin states in a quantum dot27. The magnetic-field-induced zero-bias peaks persist up to magnetic fields as large as B = 630 mT. We currently do not understand the physical mechanism of these magnetic-field-induced zero-bias peaks, although it is possible that they are related to the unique spin-momentum locking on the surface of topological insulators. In this case, it may be more energetically favorable to create a multi-particle triplet state than a single-particle spin-1/2 state. To our knowledge, no theoretical and experimental research has been reported on the subject and further studies are required to understand the physics of possible singlet-triplet transitions in topological insulator nanowires. Pikulin et al. pointed out in their simulation studies that weak antilocalization by disorder can also be a source of zero-bias conductance peaks at non-zero magnetic fields which break time-reversal symmetry29. However, this scenario is only possible when the 1D system has particle-hole symmetry resulting from superconductivity. Without the particle-hole symmetry, weak antilocalization effects should disappear when a magnetic field breaks time-reversal symmetry. The behavior of magnetic-field-induced zero-bias peaks persisting up to B = 630 mT in our device cannot be explained by a weak antilocalization effect, considering the absence of superconductivity. Moreover, lowering background conductance by increasing the tunnel barriers between electrodes and nanowires by a gate voltage is expected to suppress the zero-bias peaks originating from weak antilocalization. Our observation is opposite to this scenario: zero-bias peaks are absent in the gate voltage regions of Vg ≥ −40 V where conductance is higher, but more prominent as the gate voltage drops below −50 V and conductance decreases. This observation implies that weak antilocalization is not the origin of the zero-bias peaks in our device.


In conclusion, we have observed zero-bias conductance peaks in non-superconducting transport through a topological insulator nanowire contacted by source-drain electrodes. The logarithmic temperature dependence and splitting of the peaks with magnetic fields strongly imply that the zero-bias peaks occur from Kondo-like origins in a quantum dot. Additional features differing from typical Kondo effects in quantum dots such as high background conductance (>2 e2/h) and absence of even-odd parity behavior were observed, which may be consistent with a singlet-triplet Kondo effect and related to the topological nature of the nanowires.


Device fabrication and measurement

Topological insulator nanowires were obtained by mechanical exfoliation (‘scotch tape method’) from bulk crystals of Bi1.33Sb0.67Se3, which were grown by a modified floating zone method27. After mechanical exfoliations of bulk crystals onto 300 nm SiO2/highly n-doped Si substrates, the nanowires were found under optical microscope. The dimensions of nanowires were measured by Atomic Force Microscopy and Scanning Electron Microscopy. Electron beam lithography and metal (Ti/Al/Au = 2.5 nm/150 nm/10 nm) deposition were used to pattern two-terminal devices on the nanowires. Completed devices were wire-bonded and cooled-down in a commercial dilution refrigerator (base temperature = 16 mK). The electrical measurements were performed using standard ac lock-in techniques.

Additional Information

How to cite this article: Cho, S. et al. Kondo-like zero-bias conductance anomaly in a three-dimensional topological insulator nanowire. Sci. Rep. 6, 21767; doi: 10.1038/srep21767 (2016).


  1. 1

    Hasan, M. Z. & Kane, C. L. Colloquium: topological insulators. Rev. Mod. Phys. 82, 3045 (2010).

    CAS  ADS  Article  Google Scholar 

  2. 2

    Fu, L., Kane, C. L. & Mele, E. J. Topological insulators in three dimensions. Phys. Rev. Lett. 98, 106803 (2007).

    ADS  Article  Google Scholar 

  3. 3

    Zhang, H. J. et al. Topological insulators in Bi2Se3, Bi2Te3 and Sb2Te3 with a single Dirac cone on the surface. Nature Phys. 5, 438–442 (2009).

    CAS  ADS  Article  Google Scholar 

  4. 4

    Hsieh, D. et al. A tunable topological insulator in the spin helical Dirac transport regime. Nature 460, 1101–1105 (2009).

    CAS  ADS  Article  Google Scholar 

  5. 5

    Chen, Y. L. et al. Experimental realization of a three-dimensional topological insulator Bi2Te3 . Science 325, 178–181 (2009).

    CAS  ADS  Article  Google Scholar 

  6. 6

    Xia, Y. et al. Observation of a large-gap topological-insulator class with a single Dirac cone on the surface. Nature Phys. 5, 398–402 (2009).

    CAS  ADS  Article  Google Scholar 

  7. 7

    Zhang, T. et al. Experimental demonstration of topological surface states protected by time-reversal symmetry. Phys. Rev. Lett. 103, 266803 (2009).

    ADS  Article  Google Scholar 

  8. 8

    Alpichshev, Z. et al. STM imaging of electronic waves on the surface of Bi2Te3: Topologically protected surface states and hexagonal warping effects. Phys. Rev. Lett. 104, 016401 (2010).

    ADS  Article  Google Scholar 

  9. 9

    Hanaguri, T., Igarashi, K., Kawamura, M., Takagi, H. & Sasagawa, T. Momentum-resolved Landau-level spectroscopy of Dirac surface state in Bi2Se3 . Phys. Rev. B 82, 081305R (2010).

    ADS  Article  Google Scholar 

  10. 10

    Cheng, P. et al. Landau quantization of topological surface states in Bi2Se3 . Phys. Rev. Lett. 105, 076801 (2010).

    ADS  Article  Google Scholar 

  11. 11

    Beidenkopf, H. et al. Spatial fluctuations of helical Dirac fermions on the surface of topological insulators. Nature Phys. 7, 939–943 (2011).

    CAS  ADS  Article  Google Scholar 

  12. 12

    Steinberg, H., Gardner, D. R., Lee, Y. S. & Jarillo-Herrero, P. Surface state transport and ambipolar electric field effect in Bi2Se3 nanodevices. Nano Lett. 10, 5032–5036 (2010).

    CAS  ADS  Article  Google Scholar 

  13. 13

    Qu, D., Hor, Y. S., Xiong, J., Cava, R. J. & Ong, N. P. Quantum oscillations and Hall anomaly of surface states in the topological insulator Bi2Te3 . Science 329, 821–824 (2010).

    CAS  ADS  Article  Google Scholar 

  14. 14

    Xu, Y. et al. Observation of topological surface state quantum Hall effect in an intrinsic three-dimensional topological insulator. Nature Phys. 10, 956–963 (2014).

    CAS  ADS  Article  Google Scholar 

  15. 15

    Analytis, J. G. et al. Two-dimensional surface state in the quantum limit of a topological insulator. Nature Phys. 6, 960–964 (2010).

    CAS  ADS  Article  Google Scholar 

  16. 16

    Kim, D. et al. Surface conduction of topological Dirac electrons in bulk insulating Bi2Se3 . Nature Phys. 8, 459–463 (2012).

    ADS  Google Scholar 

  17. 17

    Chen, J. et al. Gate_voltage control of chemical potential and weak antilocalization in Bi2Se3 . Phys. Rev. Lett. 105, 176602 (2010).

    CAS  ADS  Article  Google Scholar 

  18. 18

    Checkelsky, J. G., Hor, Y. S., Cava, R. J. & Ong, N. P. Surface state conduction observed in voltage-tuned crystals of the topological insulator Bi2Se3 . Phys. Rev. Lett. 106, 196801 (2010).

    ADS  Article  Google Scholar 

  19. 19

    Yoshimi, R. et al. Quantum Hall effect on top and bottom surface states of topological insulator (Bi1−x Sb x )2Te3 films. Nature Commun. 6, 6627 10.1038/ncomms7627 (2015).

    CAS  ADS  Article  Google Scholar 

  20. 20

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

    CAS  ADS  Article  Google Scholar 

  21. 21

    Cho, S. et al. Aharonov–Bohm oscillations in a quasi-ballistic three-dimensional topological insulator nanowire. Nat. Commun. 6, 7634 10.1038/ncomms8634 (2015).

    ADS  Article  PubMed  PubMed Central  Google Scholar 

  22. 22

    Cho, S. et al. Topological Insulator Quantum Dot with Tunable Barriers. Nano Lett., 12, 469–472 (2012).

    CAS  ADS  Article  Google Scholar 

  23. 23

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

  24. 24

    de Juan, F., Ilan, R. & Bardarson, J. H. Robust Transport Signatures of Topological Superconductivity in Topological Insulator Nanowires, Phys. Rev. Lett. 113, 107003 (2014).

    ADS  Article  Google Scholar 

  25. 25

    Mourik, V. et al. Signatures of Majorana Fermions in Hybrid Superconductor-Semiconductor Nanowire Devices. Science 336, 1003–1007 (2012)

    CAS  ADS  Article  Google Scholar 

  26. 26

    Nadj-Perge, S. et al. Observation of Majorana fermions in ferromagnetic atomic chains on a superconductor, Science 346, 602–607 (2014)

    CAS  ADS  Article  Google Scholar 

  27. 27

    Sasaki, S. et al. Kondo effect in an integer-spin quantum dot. Nature 405, 764–767 (2000).

    CAS  ADS  Article  Google Scholar 

  28. 28

    Zareyan, M., Belzig, W., Nazarov, Yu & V. Superconducting proximity effect in clean ferromagnetic layers. Phys. Rev. B 65, 184505 (2002).

    ADS  Article  Google Scholar 

  29. 29

    Pikulin, D. et al. A zero-voltage conductance peak from weak antilocalization in a Majorana nanowire. New J. Phys. 14, 125011 (2012).

    ADS  Article  Google Scholar 

  30. 30

    Cho, S. et al. Symmetry protected Josephson supercurrents in three-dimensional topological insulators. Nat. Commun. 4, 1689 10.1038/ncomms2701 (2013).

    CAS  ADS  Article  PubMed  Google Scholar 

  31. 31

    Cho, S., Butch, N. P., Paglione, J. & Fuhrer, M. S. Insulating behavior in ultrathin bismuth selenide field effect transistors. Nano Lett. 11, 1925–1927 (2011).

    CAS  ADS  Article  Google Scholar 

  32. 32

    Kong, D. et al. Rapid surface oxidation as a source of surface degradation factor for Bi2Se3 . ACS Nano 5, 4698–4703 (2011).

    CAS  Article  Google Scholar 

  33. 33

    KÖhler, H. & WÖchner, E. The g-factor of the conduction electrons in Bi2Se3 . Phys. Status Solidi B 67, 665 (1975).

    ADS  Article  Google Scholar 

  34. 34

    Cronenwett, S. M. et al. Low-temperature fate of the 0.7 structure in a point contact: a Kondo-like correlated state in an open system, Phys. Rev. Lett. 88, 226805 (2002).

    CAS  ADS  Article  Google Scholar 

  35. 35

    Nygård, J. et al. Kondo physics in carbon nanotubes, Nature 408, 342–346 (2000).

    ADS  Article  Google Scholar 

  36. 36

    van der Wiel, W. G. et al. The Kondo effect in the unitary limit, Science 289, 2105–2108 (2000).

    CAS  ADS  Article  Google Scholar 

  37. 37

    Cha, J. et al. Magnetic doping and Kondo effect in Bi2Se3 nanoribbons, Nano Lett. 10, 1076–1081 (2010).

    CAS  ADS  Article  Google Scholar 

  38. 38

    Liang, C. T. et al. Experimental evidence for Coulomb charging effects in an open quantum dot at zero magnetic field. Phys. Rev. Lett. 81, 3507 (1998).

    CAS  ADS  Article  Google Scholar 

  39. 39

    Amasha, S. et al. Coulomb Blockade in an open quantum dot. Phys. Rev. Lett. 107, 216804 (2011).

    CAS  ADS  Article  Google Scholar 

  40. 40

    Tkachenko, O. A. et al. Coulomb charging effects in an open quantum dot device. J. Phys.: Condens. Matter 13, 9515 (2001).

    CAS  ADS  Google Scholar 

  41. 41

    Maurer, S. M. et al. Coulomb blockade fluctuations in strongly coupled quantum dots. Phys. Rev. Lett. 83, 1403 (1999).

    CAS  ADS  Article  Google Scholar 

  42. 42

    Lee, J. T. et al. Unconventional Kondo effect in redox active single organic macrocyclic transistors, J. Am. Chem. Soc. 133, 19547–19552 (2011).

    CAS  Article  Google Scholar 

  43. 43

    Schmid, J. et al. Absence of odd-even parity behavior for Kondo resonances in quantum dots, Phys. Rev. Lett. 84, 5824 (2000).

    CAS  ADS  Article  Google Scholar 

Download references


N.M. and S.C. acknowledge support from the ONR under grant N0014-11-1-0728 and N00014-14-1-0338. S.C acknowledges support from the National Research Foundation of Korea(NRF) under grant NRF-2015R1D1A1A02061588 and 2011-0030046, and support from KAIST High Risk High Return Project (HRHRP) and KAIST-funded K-Valley RED&B Project for 2015. Device fabrication was carried out in the Frederick Seitz Materials Research Laboratory Central Research Facilities, University of Illinois. The work at BNL was supported by the US Department of Energy, Office of Basic Energy Sciences, under contract DE-SC00112704. S.C. acknowledges useful discussions with H. Sim and E.G. Moon.

Author information




S.C. fabricated the devices and performed the electrical measurements. R.Z., J.S. and G.G. grew the bulk TI crystal. S.C. and N.M. analyzed the data and wrote the paper.

Corresponding authors

Correspondence to Sungjae Cho or Nadya Mason.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Rights and permissions

This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Cho, S., Zhong, R., Schneeloch, J. et al. Kondo-like zero-bias conductance anomaly in a three-dimensional topological insulator nanowire. Sci Rep 6, 21767 (2016).

Download citation


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links