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Chiral molecular intercalation superlattices

Nature volume 606, pages 902–908 (2022)Cite this article

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Abstract

The discovery of chiral-induced spin selectivity (CISS) opens up the possibility to manipulate spin orientation without external magnetic fields and enables new spintronic device designs1,2,3,4. Although many approaches have been explored for introducing CISS into solid-state materials and devices, the resulting systems so far are often plagued by high inhomogeneity, low spin selectivity or limited stability, and have difficulties in forming robust spintronic devices5,6,7,8. Here we report a new class of chiral molecular intercalation superlattices (CMIS) as a robust solid-state chiral material platform for exploring CISS. The CMIS were prepared by intercalating layered two-dimensional atomic crystals (2DACs) (such as TaS2 and TiS2) with selected chiral molecules (such as R-α-methylbenzylamine and S-α-methylbenzylamine). The X-ray diffraction and transmission electron microscopy studies demonstrate highly ordered superlattice structures with alternating crystalline atomic layers and self-assembled chiral molecular layers. Circular dichroism studies show clear chirality-dependent signals between right-handed (R-) and left-handed (S-) CMIS. Furthermore, by using the resulting CMIS as the spin-filtering layer, we create spin-selective tunnelling junctions with a distinct chirality-dependent tunnelling current, achieving a tunnelling magnetoresistance ratio of more than 300 per cent and a spin polarization ratio of more than 60 per cent. With a large family of 2DACs of widely tunable electronic properties and a vast selection of chiral molecules of designable structural motifs, the CMIS define a rich family of artificial chiral materials for investigating the CISS effect and capturing its potential for new spintronic devices.

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Fig. 1: Schematic drawings of CISS and the preparation of CMIS.
Fig. 2: Structural characterizations of R-MBA and S-MBA intercalation superlattices.
Fig. 3: Optical characterizations of R-MBA and S-MBA intercalation superlattices.
Fig. 4: STJs made from R-CMIS and S-CMIS.
Fig. 5: Temperature-dependent transport characteristics of a STJ with S-CMIS.

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author on reasonable request.

References

  1. Ray, K., Ananthavel, S. P., Waldeck, D. H. & Naaman, R. Asymmetric scattering of polarized electrons by organized organic films of chiral molecules. Science 283, 814–816 (1999).

    Article  ADS  CAS  PubMed  Google Scholar 

  2. Naaman, R. & Waldeck, D. H. Spintronics and chirality: spin selectivity in electron transport through chiral molecules. Annu. Rev. Phys. Chem. 66, 263–281 (2015).

    Article  ADS  CAS  PubMed  Google Scholar 

  3. Medina, E., González-Arraga, L. A., Finkelstein-Shapiro, D., Berche, B. & Mujica, V. Continuum model for chiral induced spin selectivity in helical molecules. J. Chem. Phys. 142, 194308 (2015).

    Article  ADS  PubMed  Google Scholar 

  4. Dalum, S. & Hedegård, P. Theory of chiral induced spin selectivity. Nano Lett. 19, 5253–5259 (2019).

    Article  ADS  CAS  PubMed  Google Scholar 

  5. Kiran, V. et al. Helicenes—a new class of organic spin filter. Adv. Mater. 28, 1957–1962 (2016).

    Article  CAS  PubMed  Google Scholar 

  6. Lu, H. et al. Spin-dependent charge transport through 2D chiral hybrid lead-iodide perovskites. Sci. Adv. 5, eaay0571 (2019).

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  7. Aragonès, A. C. et al. Measuring the spin-polarization power of a single chiral molecule. Small 13, 1602519 (2017).

    Article  Google Scholar 

  8. Lu, H. et al. Highly distorted chiral two-dimensional tin iodide perovskites for spin polarized charge transport. J. Am. Chem. Soc. 142, 13030–13040 (2020).

    Article  CAS  PubMed  Google Scholar 

  9. Gardner, M. The Ambidextrous Universe: Mirror Asymmetry and Time-Reversed Worlds (Penguin Books, 1964).

  10. Naaman, R. & Waldeck, D. H. Chiral-induced spin selectivity effect. J. Phys. Chem. Lett. 3, 2178–2187 (2012).

    Article  CAS  PubMed  Google Scholar 

  11. Inui, A. et al. Chirality-induced spin-polarized state of a chiral crystal CrNb3S6. Phys. Rev. Lett. 124, 166602 (2020).

    Article  ADS  CAS  PubMed  Google Scholar 

  12. Shiota, K. et al. Chirality-induced spin polarization over macroscopic distances in chiral disilicide crystals. Phys. Rev. Lett. 127, 126602 (2021).

    Article  ADS  CAS  PubMed  Google Scholar 

  13. Sung, B., De La Cotte, A. & Grelet, E. Chirality-controlled crystallization via screw dislocations. Nat. Commun. 9, 1405 (2018).

    Article  ADS  PubMed  PubMed Central  Google Scholar 

  14. Ziv, A. et al. AFM-based spin-exchange microscopy using chiral molecules. Adv. Mater. 31, 1904206 (2019).

    Article  CAS  Google Scholar 

  15. Chen, Z. et al. Chiral self-assembly of terminal alkyne and selenium clusters organic-inorganic hybrid. Nano Res. 15, 2741–2745 (2022).

    Article  ADS  CAS  Google Scholar 

  16. Kim, Y. H. et al. Chiral-induced spin selectivity enables a room-temperature spin light-emitting diode. Science 371, 1129–1133 (2021).

    Article  ADS  CAS  PubMed  Google Scholar 

  17. Leng, K., Fu, W., Liu, Y., Chhowalla, M. & Loh, K. P. From bulk to molecularly thin hybrid perovskites. Nat. Rev. Mater. 5, 482–500 (2020).

    Article  ADS  CAS  Google Scholar 

  18. Yang, S. H., Naaman, R., Paltiel, Y. & Parkin, S. S. P. Chiral spintronics. Nat. Rev. Phys. 3, 328–343 (2021).

    Article  Google Scholar 

  19. Geim, A. K. et al. Two-dimensional atomic crystals. Proc. Natl Acad. Sci. USA 102, 10451–10453 (2005).

    Article  PubMed  PubMed Central  Google Scholar 

  20. Chhowalla, M. et al. The chemistry of two-dimensional layered transition metal dichalcogenide nanosheets. Nat. Chem. 5, 263–275 (2013).

    Article  PubMed  Google Scholar 

  21. Huang, L. et al. Coherent, atomically thin transition-metal dichalcogenide superlattices with engineered strain. Science 359, 1131–1136 (2018).

    Article  ADS  PubMed  Google Scholar 

  22. Kang, K. et al. Layer-by-layer assembly of two-dimensional materials into wafer-scale heterostructures. Nature 550, 229–233 (2017).

    Article  ADS  PubMed  Google Scholar 

  23. Zhou, J. et al. Layered intercalation materials. Adv. Mater. 33, 2004557 (2021).

    Article  CAS  Google Scholar 

  24. Wang, C. et al. Monolayer atomic crystal molecular superlattices. Nature 555, 231–236 (2018).

    Article  ADS  CAS  PubMed  Google Scholar 

  25. Geim, A. K. & Grigorieva, I. V. Van der Waals heterostructures. Nature 499, 419–425 (2013).

    Article  CAS  PubMed  Google Scholar 

  26. He, Q. et al. In-situ probing molecular intercalation in two-dimensional layered semiconductors. Nano Lett. 19, 6819–6826 (2019).

    Article  ADS  CAS  PubMed  Google Scholar 

  27. Ren, H., Wan, Z. & Duan, X. Van der Waals superlattices. Natl Sci. Rev. 9, nwab166 (2022).

    Article  PubMed  Google Scholar 

  28. Meyer, S. F., Howard, R. E., Stewart, G. R., Acrivos, J. V. & Geballe, T. H. Properties of intercalated 2H-NbSe2, 4Hb-TaS2, and 1T-TaS2. J. Chem. Phys. 62, 4411–4419 (1974).

    Article  ADS  Google Scholar 

  29. Zong, P. A. et al. Flexible foil of hybrid TaS2/organic superlattice: fabrication and electrical properties. Small 16, 1901901 (2020).

    Article  CAS  Google Scholar 

  30. Nagelberg, A. S. & Worrell, W. L. A thermodynamic study of sodium-intercalated TaS2 and TiS2. J. Solid State Chem. 29, 345–354 (1979).

    Article  ADS  CAS  Google Scholar 

  31. Peng, J. et al. Very large-sized transition metal dichalcogenides monolayers from fast exfoliation by manual shaking. J. Am. Chem. Soc. 139, 9019–9025 (2017).

    Article  CAS  PubMed  Google Scholar 

  32. Schöllhorn, R. & Weiss, A. Cation exchange reactions and layer solvate complexes of ternary phases MxMoS2. J. Less-Common Met. 36, 229–236 (1974).

    Article  Google Scholar 

  33. Hovden, R. et al. Atomic lattice disorder in charge-density-wave phases of exfoliated dichalcogenides (1T-TaS2). Proc. Natl Acad. Sci. USA 113, 11420–11424 (2016).

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  34. Lee, C. et al. Anomalous lattice vibrations of single- and few-layer MoS2. ACS Nano 4, 2695–2700 (2010).

    Article  CAS  PubMed  Google Scholar 

  35. Pan, J. et al. Enhanced superconductivity in restacked TaS2 nanosheets. J. Am. Chem. Soc. 139, 4623–4626 (2017).

    Article  CAS  PubMed  Google Scholar 

  36. Wu, J. et al. Acid-assisted exfoliation toward metallic sub-nanopore TaS2 monolayer with high volumetric capacitance. J. Am. Chem. Soc. 140, 493–498 (2018).

    Article  CAS  PubMed  Google Scholar 

  37. Wang, Y. et al. Probing photoelectrical transport in lead halide perovskites with van der Waals contacts. Nat. Nanotechnol. 15, 768–775 (2020).

    Article  ADS  CAS  PubMed  Google Scholar 

  38. Göhler, B. et al. Spin selectivity in electron transmission through self-assembled monolayers of double-stranded DNA. Science 331, 894–897 (2011).

    Article  ADS  PubMed  MATH  Google Scholar 

  39. Castellanos-Gomez, A. et al. Deterministic transfer of two-dimensional materials by all-dry viscoelastic stamping. 2D Mater. 1, 011002 (2014).

    Article  CAS  Google Scholar 

  40. Chua, R. et al. Room temperature ferromagnetism of monolayer chromium telluride with perpendicular magnetic anisotropy. Adv. Mater. 33, 2103360 (2021).

    Article  CAS  Google Scholar 

  41. Liu, T. et al. Linear and nonlinear two-terminal spin-valve effect from chirality-induced spin selectivity. ACS Nano 14, 15983–15991 (2020).

    Article  PubMed  Google Scholar 

  42. Klein, D. R. et al. Probing magnetism in 2D van der Waals crystalline insulators via electron tunneling. Science 360, 1218–1222 (2018).

    Article  ADS  CAS  PubMed  Google Scholar 

  43. Wang, Z. et al. Tunneling spin valves based on Fe3GeTe2/hBN/Fe3GeTe2 van der Waals heterostructures. Nano Lett. 18, 4303–4308 (2018).

    Article  ADS  CAS  PubMed  Google Scholar 

  44. Song, T. et al. Giant tunneling magnetoresistance in spin-filter van der Waals heterostructures. Science 360, 1214–1218 (2018).

    Article  ADS  CAS  PubMed  Google Scholar 

  45. Das, T. K., Tassinari, F., Naaman, R. & Fransson, J. Temperature-dependent chiral-induced spin selectivity effect: experiments and theory. J. Phys. Chem. C 126, 3257–3264 (2022).

    Article  CAS  Google Scholar 

  46. Du, G. F., Fu, H. H. & Wu, R. Vibration-enhanced spin-selective transport of electrons in the DNA double helix. Phys. Rev. B 102, 35431 (2020).

    Article  ADS  CAS  Google Scholar 

  47. Fransson, J. Vibrational origin of exchange splitting and chiral-induced spin selectivity. Phys. Rev. B 102, 235416 (2020).

    Article  ADS  CAS  Google Scholar 

  48. Yildiz, A., Serin, N., Serin, T. & Kasap, M. Crossover from nearest-neighbor hopping conduction to Efros–Shklovskii variable-range hopping conduction in hydrogenated amorphous silicon films. Jpn. J. Appl. Phys. 48, 111203 (2009).

    Article  ADS  Google Scholar 

  49. Julliere, M. Tunneling between ferromagnetic films. Phys. Lett. A 54, 225–226 (1975).

    Article  ADS  Google Scholar 

  50. Shang, C. H., Nowak, J., Jansen, R. & Moodera, J. S. Temperature dependence of magnetoresistance and surface magnetization in ferromagnetic tunnel junctions. Phys. Rev. B 58, R2917–R2920 (1998).

    Article  ADS  CAS  Google Scholar 

  51. Luxa, J. et al. 2H→1T phase engineering of layered tantalum disulfides in electrocatalysis: oxygen reduction reaction. Chem. Eur. J. 23, 8082–8091 (2017).

    Article  CAS  PubMed  Google Scholar 

  52. Mishra, S. et al. Spin filtering along chiral polymers. Angew. Chem. Int. Ed. 59, 14671–14676 (2020).

    Article  CAS  Google Scholar 

  53. Ma, J. et al. Chiral 2D perovskites with a high degree of circularly polarized photoluminescence. ACS Nano 13, 3659–3665 (2019).

    Article  CAS  PubMed  Google Scholar 

  54. Ghosh, K. B. et al. Controlling chemical selectivity in electrocatalysis with chiral CuO-coated electrodes. J. Phys. Chem. C 123, 3024–3031 (2019).

    Article  CAS  Google Scholar 

  55. Mondal, A. K. et al. Spin filtering in supramolecular polymers assembled from achiral monomers mediated by chiral solvents. J. Am. Chem. Soc. 143, 7189–7195 (2021).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  56. Kettner, M. et al. Chirality-dependent electron spin filtering by molecular monolayers of helicenes. J. Phys. Chem. Lett. 9, 2025–2030 (2018).

    Article  CAS  PubMed  Google Scholar 

  57. Kettner, M. et al. Spin filtering in electron transport through chiral oligopeptides. J. Phys. Chem. C 119, 14542–14547 (2015).

    Article  CAS  Google Scholar 

  58. Mishra, D. et al. Spin-dependent electron transmission through bacteriorhodopsin embedded in purple membrane. Proc. Natl Acad. Sci. USA 110, 14872–14876 (2013).

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  59. Mathew, S. P., Mondal, P. C., Moshe, H., Mastai, Y. & Naaman, R. Non-magnetic organic/inorganic spin injector at room temperature. Appl. Phys. Lett. 105, 242408 (2014).

    Article  ADS  Google Scholar 

  60. Mondal, P. C. et al. Chiral conductive polymers as spin filters. Adv. Mater. 27, 1924–1927 (2015).

    Article  CAS  PubMed  Google Scholar 

  61. Varade, V. et al. Bacteriorhodopsin based non-magnetic spin filters for biomolecular spintronics. Phys. Chem. Chem. Phys. 20, 1091–1097 (2018).

    Article  CAS  PubMed  Google Scholar 

  62. Sang, Y. et al. Temperature dependence of charge and spin transfer in azurin. J. Phys. Chem. C 125, 9875–9883 (2021).

    Article  CAS  Google Scholar 

  63. Kulkarni, C. et al. Highly efficient and tunable filtering of electrons’ spin by supramolecular chirality of nanofiber-based materials. Adv. Mater. 32, 1904965 (2020).

    Article  CAS  Google Scholar 

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Acknowledgements

We acknowledge the helpful discussions with T. Liu, and Electron Imaging Center for NanoMachines (EICN) at California NanoSystems Institute (CNSI) and Nanoelectronics Research Facility (NRF) at UCLA for technical support. The cross-sectional STEM experiments were partly conducted using the facilities and instrumentation at the UCI Irvine Materials Research Institute (IMRI), which is supported in part by the National Science Foundation through the UCI Materials Research Science and Engineering Center (DMR-2011967). Xiangfeng Duan acknowledges partial support from the US Department of Energy, Office of Basic Energy Sciences, Division of Materials Science and Engineering through award DE-SC0018828. Y.H. acknowledges financial support from the Office of Naval Research through award N00014-18-1-2491. X.P. acknowledges financial support from US Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under grant no. DE-SC0014430. Xidong Duan acknowledges the support from the National Natural Science Foundation of China (grant number 51872086) and the Innovative Research Groups of Hunan Province (grant 2020JJ1001). Z.S. was supported by the Czech Science Foundation (GACR no. 20-16124J).

Author information

Author notes

  1. These authors contributed equally: Qi Qian, Huaying Ren

Authors and Affiliations

  1. Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA

    Qi Qian, Huaying Ren, Jingyuan Zhou, Zhong Wan, Peiqi Wang & Xiangfeng Duan

  2. Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, USA

    Jingxuan Zhou, Jin Cai & Yu Huang

  3. Department of Materials Science and Engineering, University of California, Irvine, Irvine, CA, USA

    Xingxu Yan & Xiaoqing Pan

  4. Hunan Key Laboratory of Two-Dimensional Materials, State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, China

    Bailing Li, Bo Li & Xidong Duan

  5. Department of Inorganic Chemistry, University of Chemistry and Technology, Prague, Prague, Czech Republic

    Zdenek Sofer

  6. Department of Physics and Astronomy, University of California, Irvine, Irvine, CA, USA

    Xiaoqing Pan

  7. Irvine Materials Research Institute, University of California, Irvine, Irvine, CA, USA

    Xiaoqing Pan

  8. California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA

    Yu Huang & Xiangfeng Duan

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  1. Qi Qian
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Contributions

Xiangfeng Duan conceived the research. H.R., Z.W. and Q.Q. designed the experiments. H.R. developed synthetic methods of CMIS, performed XRD, AFM, CD and Raman characterizations and analysed the data. Q.Q. and Z.W. performed device fabrication, electrical measurements and data analysis with help from P.W., and Jingyuan Zhou contributed to discussions and helped analyse the data. Jingxuan Zhou performed the TEM characterization. X.Y. and X.P. performed the cross-sectional STEM characterization. Bailing Li, Bo Li and Xidong Duan prepared Cr3Te4 nanoplates. Z.S. provided H-TaS2 and T-TaS2 crystals. J.C. performed the SEM characterization. Y.H. and Xiangfeng Duan supervised the research. Z.W., H.R., Q.Q. and Xiangfeng Duan co-wrote the manuscript with input from all of the authors. All authors discussed the results and commented on the manuscript.

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Correspondence to Xiangfeng Duan.

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Additional information

Extended data

is available for this paper at https://doi.org/10.1038/s41586-022-04846-3.

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Extended data figures and tables

Extended Data Fig. 1 Characterizations of CMIS layer expansion.

a, The evolution of XRD patterns of R-MBA intercalated H-TaS2 as a function of reaction time. The XRD patterns show that the original set of (00l) peaks gradually dwindle and eventually completely vanish with increasing intercalation duration, whereas a new set of (00l) peaks of the intercalation materials grows and eventually evolves into the only set of diffraction peaks after 48 h of intercalation, indicating the complete intercalation to form phase-pure intercalation superlattices. b, XRD patterns of the R-DMPEA/H-TaS2 and S-DMPEA/H-TaS2 CMIS and intrinsic H-TaS2. c, XRD patterns of the L-histidine/H-TaS2 CMIS and intrinsic H-TaS2. XRD results show that diffraction peaks of (00l) planes of DMPEA/H-TaS2 and L-histidine/H-TaS2 are considerably shifted to lower diffraction angles with an interlayer expansion of 11.6 Å and 4.5 Å, respectively, when compared with those of the intrinsic bulk H-TaS2 (b), suggesting the successful intercalation of these molecules in H-TaS2.

Extended Data Fig. 2 STEM image and SAED patterns of the intrinsic H-TaS2.

a, STEM image of the basal plane of intrinsic H-TaS2. Blue and yellow dots represent tantalum and sulfur, respectively. Scale bar, 1 nm. b, SAED patterns of intrinsic H-TaS2. Scale bar, 2 nm−1. The in-plane lattice parameter remains unchanged between H-TaS2 and MBA/TaS2 CMIS, confirming that the H-TaS2 host layers retain the original atomic structure with no notable lattice distortion after the formation of CMIS.

Extended Data Fig. 3 CD spectra of CMIS with different chiral molecule intercalations.

a, CD spectra of chiral molecules dispersed in IPA and pure IPA. All the CD spectra are acquired by using quartz cuvette. The concentrations of R-MBA and S-MBA molecules are about 0.5 mmol ml−1. b, CD spectra of R-DMPEA/H-TaS2 and S-DMPEA/H-TaS2 CMIS and intrinsic H-TaS2. c, CD spectra of L-histidine/H-TaS2 CMIS and intrinsic H-TaS2.

Extended Data Fig. 4 Further characterizations of Cr3Te4 and non-chiral junctions.

a, Temperature-dependent anomalous Hall resistance of a representative Cr3Te4 nanoplate, showing a coercive field of 0.5 T at 10 K and a Curie temperature of around 200 K. The coercive field is consistent with the abrupt changes of the conductivity observed in the STJ device. The large hysteresis loops of the anomalous Hall resistance suggest a robust out-of-plane ferromagnetic ordering at low temperature, which is required for the vertical STJ. b, Two-terminal resistance of a typical Cr3Te4 nanoplate at 10 K, showing typical resistances <3 kΩ. c, The zoomed-in plot of b between 2.4 and 2.6 kΩ, with a <100 Ω (<1% of the resistance of Cr3Te4) smooth change of the resistance around the coercive field. The resistance variation around the coercive field is about 104 times smaller than the resistance change observed in the STJ, suggesting that the tunnelling conductance across the STJ is dominated by vertical transport across the superlattices and the serial resistance of the lateral transport through the Cr3Te4 nanoplate is negligible. d,e, Magnetic-field-dependent tunnelling current measurements of an intrinsic H-TaS2/Cr3Te4 (d) and a rac-MBA/H-TaS2/Cr3Te4 device (e), respectively. Here rac-MBA is the racemic mixture of R-MBA and S-MBA and the bias voltage applied is 0.1 V. The intrinsic H-TaS2/Cr3Te4 device showed around three orders of magnitude higher current than that of the CMIS device, which is not surprising because both Cr3Te4 and TaS2 are either metal or semimetal. The device with rac-MBA/H-TaS2 intercalation superlattice showed a similar current level to that of the CMIS devices. In both cases, the tunnelling magnetoresistance experiments do not show apparent changes with magnetic field, which is clearly different from that with the CMIS devices.

Extended Data Fig. 5 Comparison between 2-terminal and 4-terminal measurements.

a,b Schematic drawing of the 2-terminal and 4-terminal measurement set-ups, respectively. c, I–V measurements of the 2-terminal and 4-terminal configurations under different magnetic field directions. d, Magnetic-field-dependent tunnelling conductance determined from the 2-terminal and 4-terminal configurations at the bias of 0.1 V. 2T, 2-terminal; 4T, 4-terminal. Our 4-terminal and 2-terminal measurements essentially gave the same results, indicating negligible contribution from the contact resistance or the series resistance from the Cr3Te4 and H-TaS2. Compared with the overall resistance of the CMIS junction (typically larger than 10 MΩ at 10 K), the contribution from the contact and series resistance is estimated to be only about 0.1% of the total measured resistance in the 2-terminal measurement and, thus, would not affect our interpretation.

Extended Data Fig. 6 Bias-dependent magnetoresistance ratio measured at different temperatures.

a–d, Bias-dependent I–V at different temperatures. e,f, The corresponding bias-dependent magnetoresistance ratio MR%. The MR% values at the low-bias regime (<0.050 V) are omitted, which cannot be reliably determined owing to low tunnelling current.

Extended Data Fig. 7 Further temperature-dependent studies for MBA/H-TaS2 STJ devices.

a, Additional temperature-dependent curves for S-MBA/H-TaS2 STJ devices. Data were taken on the same device as shown in Figs. 4d,f and 5. b, The corresponding temperature-dependent conductance of the high current state and the low current state. c, Temperature-dependent GSI. The black dashed line is the fitting between 50 K and 300 K with the activation function of \({G}_{{\rm{SI}}}(T){{=G}_{0}{\rm{e}}}^{\frac{-{E}_{{\rm{A}}}}{{k}_{{\rm{B}}}T}}\), in which G0 is a normalization factor and kB is the Boltzmann constant. The resulting activation energy EA = 12 meV. d, Temperature-dependent conductance of the high current state and the low current state. Data were taken on the same device as shown in Fig. 4c,e for R-MBA/H-TaS2 CMIS. e, Temperature-dependent GSI. The black dashed line is the fitting with the Arrhenius function, which yields an activation energy EA = 16 meV. The activation energy is slightly higher than the S-MBA/H-TaS2 CMIS, which is consistent with the smaller conductivity observed in this device.

Extended Data Fig. 8 Temperature-dependent polarization for different devices.

The temperature-dependent polarization shows a similar trend between different devices, in which the polarization reduces with increasing temperature. Device 1 and Device 2 are reported in Fig. 4c,d, respectively.

Extended Data Table 1 Comparison of the CISS-induced polarization ratio measured with different methods
Full size table
Extended Data Table 2 Comparison of the CISS-induced magnetoresistance (MR%) and polarization ratio measured through the magnetic field sweeping loop in the magnetic tunnelling deviceComparison of the CISS-induced magnetoresistance (MR%) and polarization ratio measured through the magnetic field sweeping loop in the magnetic tunnelling device
Full size table

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Qian, Q., Ren, H., Zhou, J. et al. Chiral molecular intercalation superlattices. Nature 606, 902–908 (2022). https://doi.org/10.1038/s41586-022-04846-3

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