Skip to main content

Thank you for visiting nature.com. 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.

  • Article
  • Published:

Ferroelectric order in individual nanometre-scale crystals

Abstract

Ferroelectricity in finite-dimensional systems continues to arouse interest, motivated by predictions of vortex polarization states and the utility of ferroelectric nanomaterials in memory devices, actuators and other applications. Critical to these areas of research are the nanoscale polarization structure and scaling limit of ferroelectric order, which are determined here in individual nanocrystals comprising a single ferroelectric domain. Maps of ferroelectric structural distortions obtained from aberration-corrected transmission electron microscopy, combined with holographic polarization imaging, indicate the persistence of a linearly ordered and monodomain polarization state at nanometre dimensions. Room-temperature polarization switching is demonstrated down to ~5 nm dimensions. Ferroelectric coherence is facilitated in part by control of particle morphology, which along with electrostatic boundary conditions is found to determine the spatial extent of cooperative ferroelectric distortions. This work points the way to multi-Tbit/in2 memories and provides a glimpse of the structural and electrical manifestations of ferroelectricity down to its ultimate limits.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Ferroelectric distortions of the GeTe and BaTiO3 conventional unit cells.
Figure 2: Atomic-resolution reconstructed phase images and polar displacement maps of individual GeTe monocrystalline nanoparticles.
Figure 3: Atomic-resolution reconstructed phase images and titanium displacement maps of individual BaTiO3 monocrystalline nanocubes.
Figure 4: Direct polarization imaging of individual BaTiO3 nanocubes with off-axis electron holography.
Figure 5: Temperature-dependent PFM measurements of individual BaTiO3 nanocubes.
Figure 6: Atomic PDF analysis of GeTe and BaTiO3 nanocrystal ensembles.

Similar content being viewed by others

References

  1. Bawendi, M. G., Steigerwald, M. L. & Brus, L. E. The quantum mechanics of larger semiconductor clusters (quantum dots). Annu. Rev. Phys. Chem. 41, 477–496 (1990).

    Article  CAS  Google Scholar 

  2. Law, M., Goldberger, J. & Yang, P. Semiconductor nanowires and nanotubes. Annu. Rev. Mater. Sci. 34, 83–122 (2004).

    Article  CAS  Google Scholar 

  3. Murray, C. B. et al. Colloidal synthesis of nanocrystals and nanocrystal superlattices. IBM J. Res. Dev. 45, 47–56 (2001).

    Article  CAS  Google Scholar 

  4. Scott, J. F. Applications of modern ferroelectrics. Science 315, 954–959 (2007).

    Article  CAS  Google Scholar 

  5. Scott, J. F. & Paz de Araujo, C. A. Ferroelectric memories. Science 246, 1400–1405 (1989).

    Article  CAS  Google Scholar 

  6. Chattopadhyay, S., Ayyub, P., Palkar, V. R. & Multani, M. Size-induced diffuse phase transition in the nanocrystalline ferroelectric PbTiO3 . Phys. Rev. B 52, 13177–13183 (1995).

    Article  CAS  Google Scholar 

  7. Zhong, W. L., Wang, Y. G., Zhang, P. L. & Qu, B. D. Phenomenological study of the size effect on phase transitions in ferroelectric particles. Phys. Rev. B 50, 698–703 (1994).

    Article  CAS  Google Scholar 

  8. Smith, M. B. et al. Crystal structure and the paraelectric-to-ferroelectric phase transition of nanoscale BaTiO3 . J. Am. Chem. Soc. 130, 6955–6963 (2008).

    Article  CAS  Google Scholar 

  9. Petkov, V., Gateshki, M., Niederberger, M. & Ren, Y. Atomic-scale structure of nanocrystalline BaxSr1−xTiO3 (x = 1, 0.5, 0) by X-ray diffraction and the atomic pair distribution function technique. Chem. Mater. 18, 814–821 (2006).

    Article  CAS  Google Scholar 

  10. Page, K., Proffen, T., Niederberger, M. & Seshadri, R. Probing local dipoles and ligand structure in BaTiO3 nanoparticles. Chem. Mater. 22, 4386–4391 (2010).

    Article  CAS  Google Scholar 

  11. Naumov, I. I., Bellaiche, L. & Fu, H. Unusual phase transitions in ferroelectric nanodisks and nanorods. Nature 432, 737–740 (2004).

    Article  CAS  Google Scholar 

  12. Durgun, E., Ghosez, P., Shaltaf, R., Gonze, X. & Raty, J-Y. Polarization vortices in germanium telluride nanoplatelets: A theoretical study. Phys. Rev. Lett. 103, 247601 (2009).

    Article  CAS  Google Scholar 

  13. Kretschmer, R. & Binder, K. Surface effects on phase transitions in ferroelectrics and dipolar magnets. Phys. Rev. B 20, 1065–1076 (1979).

    Article  CAS  Google Scholar 

  14. Batra, I. P., Wurfel, P. & Silverman, B. D. New type of first-order phase transition in ferroelectric thin films. Phys. Rev. Lett. 30, 384–387 (1973).

    Article  CAS  Google Scholar 

  15. Morozovska, A. N., Glinchuk, M. D. & Eliseev, E. A. Phase transitions induced by confinement of ferroic nanoparticles. Phys. Rev. B 76, 014102 (2007).

    Article  Google Scholar 

  16. Urban, J. J., Yun, W. S. & Park, H. Synthesis of single-crystalline perovskite nanorods composed of barium titanate and strontium titanate. J. Am. Chem. Soc. 124, 1186–1187 (2002).

    Article  CAS  Google Scholar 

  17. Adireddy, S., Lin, C., Cao, B., Zhou, W. & Caruntu, G. Solution-based growth of monodisperse cube-like BaTiO3 colloidal nanocrystals. Chem Mater. 22, 1946–1948 (2010).

    Article  CAS  Google Scholar 

  18. Polking, M. J., Zheng, H., Ramesh, R. & Alivisatos, A. P. Controlled synthesis and size-dependent polarization domain structure of colloidal germanium telluride nanocrystals. J. Am. Chem. Soc. 133, 2044–2047 (2011).

    Article  CAS  Google Scholar 

  19. Chopra, K. L. & Bahl, S. K. Amorphous and crystalline GeTe films. I. Growth and structural behavior. J. Appl. Phys. 40, 4171–4178 (1969).

    Article  CAS  Google Scholar 

  20. Steigmeier, E. F. & Harbeke, G. Soft phonon mode and ferroelectricity in GeTe. Solid State Commun. 8, 1275–1279 (1970).

    Article  CAS  Google Scholar 

  21. Bahl, S. K. & Chopra, K. L. Amorphous versus crystalline GeTe films. II. Optical properties. J. Appl. Phys. 40, 4940–4947 (1969).

    Article  CAS  Google Scholar 

  22. Chattopadhyay, T., Boucherle, J. X. & Von Schnering, H. G. Neutron diffraction study on the structural phase transition in GeTe. J. Phys. C 20, 1431–1440 (1987).

    Article  CAS  Google Scholar 

  23. Edwards, A. H. et al. Electronic structure of intrinsic defects in crystalline germanium telluride. Phys. Rev. B 73, 045210 (2006).

    Article  Google Scholar 

  24. Lines, M. E. & Glass, A. M. Principles and Applications of Ferroelectrics and Related Materials (Clarendon, 1977).

    Google Scholar 

  25. Kwei, G. H., Lawson, A. C., Billinge, S. J. L. & Cheong, S-W. Structures of the ferroelectric phases of barium titanate. J. Phys. Chem. 97, 2368–2377 (1993).

    Article  CAS  Google Scholar 

  26. Jia, C-L. et al. Unit-cell scale mapping of ferroelectricity and tetragonality in epitaxial ultrathin ferroelectric films. Nature Mater. 6, 64–69 (2007).

    Article  CAS  Google Scholar 

  27. Jia, C-L., Urban, K.W., Alexe, M., Hesse, D. & Vrejoiu, I. Direct observation of continuous electric dipole rotation in flux-closure domains in ferroelectric Pb(Zr,Ti)O3 . Science 331, 1420–1423 (2011).

    Article  CAS  Google Scholar 

  28. Gerchberg, R. W. & Saxton, W. O. A practical algorithm for the determination of the phase from image and diffraction plane pictures. Optik 35, 237–246 (1972).

    Google Scholar 

  29. Coene, W., Janssen, G., Op de Beeck, M. & Van Dyck, D. Phase retrieval through focus variation for ultra-resolution in field-emission transmission electron microscopy. Phys. Rev. Lett. 69, 3743–3746 (1992).

    Article  CAS  Google Scholar 

  30. Lencer, D. et al. A map for phase-change materials. Nature Mater. 7, 972–977 (2008).

    Article  CAS  Google Scholar 

  31. Snykers, M., Delavignette, P. & Amelinckx, S. The domain structure of GeTe as observed by electron microscopy. Mater. Res. Bull. 7, 831–839 (1972).

    Article  CAS  Google Scholar 

  32. Merz, W. J. Double hysteresis loop of BaTiO3 at the Curie point. Phys. Rev. 91, 513–517 (1953).

    Article  CAS  Google Scholar 

  33. McCartney, M. R. & Smith, D. J. Electron holography: Phase imaging with nanometer resolution. Annu. Rev. Mater. Sci. 37, 729–767 (2007).

    Article  CAS  Google Scholar 

  34. Lichte, H., Reibold, M., Brand, K. & Lehmann, M. Ferroelectric electron holography. Ultramicroscopy 93, 199–212 (2002).

    Article  CAS  Google Scholar 

  35. Kalinin, S. V. & Bonnell, D. A. Imaging mechanism of piezoresponse force microscopy of ferroelectric surfaces. Phys. Rev. B 65, 125408 (2002).

    Article  Google Scholar 

  36. Nagarajan, V. et al. Dynamics of ferroelastic domains in ferroelectric thin films. Nature Mater. 2, 43–47 (2003).

    Article  CAS  Google Scholar 

  37. Maksymovych, P. et al. Polarization control of electron tunneling into ferroelectric surfaces. Science 324, 1421–1425 (2009).

    Article  CAS  Google Scholar 

  38. Jona, F. & Shirane, G. Ferroelectric Crystals (Dover, 1993).

    Google Scholar 

  39. Ma, W. & Hesse, D. Microstructure and piezoelectric properties of sub-80 nm high polycrystalline SrBi2Ta2O9 nanostructures within well-ordered arrays. Appl. Phys. Lett. 85, 3214–3216 (2004).

    Article  CAS  Google Scholar 

  40. Shiratori, Y., Pithan, C., Dornseiffer, J. & Waser, R. Raman scattering studies on nanocrystalline BaTiO3 part I—isolated particles and aggregates. J. Raman Spectros. 38, 1288–1299 (2007).

    Article  CAS  Google Scholar 

  41. Polking, M. J. et al. Size-dependent polar ordering in colloidal GeTe nanocrystals. Nano Lett. 11, 1147–1152 (2011).

    Article  CAS  Google Scholar 

  42. Spanier, J. E. et al. Ferroelectric phase transition in individual single-crystalline BaTiO3 nanowires. Nano Lett. 6, 735–739 (2006).

    Article  CAS  Google Scholar 

  43. Ponomareva, I., Naumov, I. I. & Bellaiche, L. Low-dimensional ferroelectrics under different electrical and mechanical boundary conditions: Atomistic simulations. Phys. Rev. B 72, 214118 (2005).

    Article  Google Scholar 

  44. Nelson, C. T. et al. Spontaneous vortex nanodomain arrays at ferroelectric heterointerfaces. Nano Lett. 11, 828–834 (2011).

    Article  CAS  Google Scholar 

  45. Schilling, A. et al. Domains in ferroelectric nanodots. Nano Lett. 9, 3359–3364 (2009).

    Article  CAS  Google Scholar 

  46. McQuaid, R. G. P., McGilly, L. J., Sharma, P., Gruverman, A. & Gregg, J. M. Mesoscale flux-closure domain formation in single-crystal BaTiO3 . Nature Commun. 2, 404 (2011).

    Article  CAS  Google Scholar 

  47. Luk’yanchuk, I. A., Schilling, A., Gregg, J. M., Catalan, G. & Scott, J. F. Origin of ferroelastic domains in free-standing single-crystal ferroelectric films. Phys. Rev. B 79, 144111 (2009).

    Article  Google Scholar 

  48. Rodriguez, B. J., Callahan, C., Kalinin, S. V. & Proksch, R. Dual-frequency resonance-tracking atomic force microscopy. Nanotechnology 18, 475504 (2007).

    Article  Google Scholar 

  49. Petkov, V. RAD, a program for analysis of X-ray diffraction data from amorphous materials for personal computers. J. Appl. Crystallogr. 22, 387–389 (1989).

    Article  CAS  Google Scholar 

  50. Farrow, C. L. et al. PDFfit2 and PDFgui: Computer programs for studying nanostructure in crystals. J. Phys. Condens. Matter 19, 335219 (2007).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

The authors would like to thank Shiva Adireddy for the synthesis of the BaTiO3 nanomaterials used in this manuscript; P. Ercius, T. Duden, Y. Ren and A. Gautam for technical assistance and helpful discussions; and H. Park for critical feedback on the manuscript. In addition, the authors gratefully acknowledge M. R. McCartney for providing scripts for the analysis of the holographic images. Access to the electron microscopy facility at the Center for Functional Nanomaterials, Brookhaven National Laboratory, is acknowledged. Work at the National Center for Electron Microscopy was supported by the US Department of Energy, Division of Materials Sciences and Division of Chemical Sciences, under contract no. DE-AC02-05CH11231. Electron holography experiments at Brookhaven National Laboratory were supported by the US Department of Energy, Division of Materials Sciences and Division of Chemical Sciences, under contract no. DE-AC02-98CH10886 and were carried out in part at the Center for Functional Nanomaterials, Brookhaven National Laboratory. Synchrotron X-ray diffraction measurements at the Advanced Photon Source were supported by the Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under Contract DE-AC02-06CH11357. Work on piezoresponse force measurements and synthesis of BaTiO3 nanostructures was supported by the National Science Foundation through grants no. NSF-MSN CAREER-1157300, no. EPS-1003897 and no. NSF-DMR-1004869. All other work was supported by the Physical Chemistry of Nanocrystals Project of the Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, of the US Department of Energy under contract no. DE-AC02-05CH11231. M.J.P. was supported by a National Science Foundation Graduate Research Fellowship and by a National Science Foundation Integrative Graduate Education and Research Traineeship fellowship.

Author information

Authors and Affiliations

Authors

Contributions

M.J.P. conceived the experiment, performed atomic-resolution TEM studies of GeTe and BaTiO3 nanocrystals and analysed the results, participated in holographic imaging experiments with M-G.H. and Y.Z., interpreted data, and wrote the manuscript. A.Y. acquired piezoresponse force data on BaTiO3 nanocubes under the supervision of G.C. Analysis of the PFM data was performed by G.C. and A.Y. V.P. acquired atomic PDF data and analysed the results, and C.F.K. assisted in the analysis of the TEM data. V.V.V performed phase image simulations for the holographic images. R.R. and A.P.A. supervised the work and provided critical feedback on the manuscript.

Corresponding authors

Correspondence to A. Paul Alivisatos or Ramamoorthy Ramesh.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Rights and permissions

Reprints and permissions

About this article

Cite this article

Polking, M., Han, MG., Yourdkhani, A. et al. Ferroelectric order in individual nanometre-scale crystals. Nature Mater 11, 700–709 (2012). https://doi.org/10.1038/nmat3371

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nmat3371

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing