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.
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References
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).
Law, M., Goldberger, J. & Yang, P. Semiconductor nanowires and nanotubes. Annu. Rev. Mater. Sci. 34, 83–122 (2004).
Murray, C. B. et al. Colloidal synthesis of nanocrystals and nanocrystal superlattices. IBM J. Res. Dev. 45, 47–56 (2001).
Scott, J. F. Applications of modern ferroelectrics. Science 315, 954–959 (2007).
Scott, J. F. & Paz de Araujo, C. A. Ferroelectric memories. Science 246, 1400–1405 (1989).
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).
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).
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).
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).
Page, K., Proffen, T., Niederberger, M. & Seshadri, R. Probing local dipoles and ligand structure in BaTiO3 nanoparticles. Chem. Mater. 22, 4386–4391 (2010).
Naumov, I. I., Bellaiche, L. & Fu, H. Unusual phase transitions in ferroelectric nanodisks and nanorods. Nature 432, 737–740 (2004).
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).
Kretschmer, R. & Binder, K. Surface effects on phase transitions in ferroelectrics and dipolar magnets. Phys. Rev. B 20, 1065–1076 (1979).
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).
Morozovska, A. N., Glinchuk, M. D. & Eliseev, E. A. Phase transitions induced by confinement of ferroic nanoparticles. Phys. Rev. B 76, 014102 (2007).
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).
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).
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).
Chopra, K. L. & Bahl, S. K. Amorphous and crystalline GeTe films. I. Growth and structural behavior. J. Appl. Phys. 40, 4171–4178 (1969).
Steigmeier, E. F. & Harbeke, G. Soft phonon mode and ferroelectricity in GeTe. Solid State Commun. 8, 1275–1279 (1970).
Bahl, S. K. & Chopra, K. L. Amorphous versus crystalline GeTe films. II. Optical properties. J. Appl. Phys. 40, 4940–4947 (1969).
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).
Edwards, A. H. et al. Electronic structure of intrinsic defects in crystalline germanium telluride. Phys. Rev. B 73, 045210 (2006).
Lines, M. E. & Glass, A. M. Principles and Applications of Ferroelectrics and Related Materials (Clarendon, 1977).
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).
Jia, C-L. et al. Unit-cell scale mapping of ferroelectricity and tetragonality in epitaxial ultrathin ferroelectric films. Nature Mater. 6, 64–69 (2007).
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).
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).
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).
Lencer, D. et al. A map for phase-change materials. Nature Mater. 7, 972–977 (2008).
Snykers, M., Delavignette, P. & Amelinckx, S. The domain structure of GeTe as observed by electron microscopy. Mater. Res. Bull. 7, 831–839 (1972).
Merz, W. J. Double hysteresis loop of BaTiO3 at the Curie point. Phys. Rev. 91, 513–517 (1953).
McCartney, M. R. & Smith, D. J. Electron holography: Phase imaging with nanometer resolution. Annu. Rev. Mater. Sci. 37, 729–767 (2007).
Lichte, H., Reibold, M., Brand, K. & Lehmann, M. Ferroelectric electron holography. Ultramicroscopy 93, 199–212 (2002).
Kalinin, S. V. & Bonnell, D. A. Imaging mechanism of piezoresponse force microscopy of ferroelectric surfaces. Phys. Rev. B 65, 125408 (2002).
Nagarajan, V. et al. Dynamics of ferroelastic domains in ferroelectric thin films. Nature Mater. 2, 43–47 (2003).
Maksymovych, P. et al. Polarization control of electron tunneling into ferroelectric surfaces. Science 324, 1421–1425 (2009).
Jona, F. & Shirane, G. Ferroelectric Crystals (Dover, 1993).
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).
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).
Polking, M. J. et al. Size-dependent polar ordering in colloidal GeTe nanocrystals. Nano Lett. 11, 1147–1152 (2011).
Spanier, J. E. et al. Ferroelectric phase transition in individual single-crystalline BaTiO3 nanowires. Nano Lett. 6, 735–739 (2006).
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).
Nelson, C. T. et al. Spontaneous vortex nanodomain arrays at ferroelectric heterointerfaces. Nano Lett. 11, 828–834 (2011).
Schilling, A. et al. Domains in ferroelectric nanodots. Nano Lett. 9, 3359–3364 (2009).
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).
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).
Rodriguez, B. J., Callahan, C., Kalinin, S. V. & Proksch, R. Dual-frequency resonance-tracking atomic force microscopy. Nanotechnology 18, 475504 (2007).
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).
Farrow, C. L. et al. PDFfit2 and PDFgui: Computer programs for studying nanostructure in crystals. J. Phys. Condens. Matter 19, 335219 (2007).
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.
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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.
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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
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DOI: https://doi.org/10.1038/nmat3371
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