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.

Coherence–incoherence and dimensional crossover in layered strongly correlated metals


The properties of an interacting electron system depend on the electron correlations and the effective dimensionality. For example, Coulomb repulsion between electrons may inhibit, or completely block, conduction by intersite electron hopping, thereby determining whether a material is a metal or an insulator1. Furthermore, correlation effects increase as the number of effective dimensions decreases; in three-dimensional systems, the low-energy electronic states behave as quasiparticles, whereas in one-dimensional systems, even weak interactions break the quasiparticles into collective excitations2. Dimensionality is particularly important for exotic low-dimensional materials where one- or two-dimensional building blocks are loosely connected into a three-dimensional whole. Here we examine two such layered metallic systems with angle-resolved photoemission spectroscopy and electronic transport measurements, and we find a crossover in the number of effective dimensions—from two to three—with decreasing temperature. This is apparent from the observation that, in the direction perpendicular to the layers, the materials have an insulating character at high temperatures but become metal-like at low temperatures, whereas transport within the layers remains metallic over the whole temperature range. We propose that this change in effective dimensionality correlates with the presence of coherent quasiparticles within the layers.

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

Access options

Rent or buy this article

Prices vary by article type



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

Figure 1: Angle-resolved photoelectron spectra of (Bi0.5Pb0.5)2Ba3Co2Oy.
Figure 2: Correlation between the ARPES and transport in (Bi0.5Pb0.5)2Ba3Co2Oy.
Figure 3: ARPES and d.c. transport in NaCo2O4.


  1. Mott, N. F. Metal-insulator Transitions (Taylor & Francis, London, 1990)

    Book  Google Scholar 

  2. Jâerome, D. & Caron, L. G. Low-dimensional Conductors and Superconductors (Plenum, New York, 1987)

    Book  Google Scholar 

  3. Maeno, Y. et al. Superconductivity in a layered perovskite without copper. Nature 372, 532–534 (1994)

    Article  ADS  CAS  Google Scholar 

  4. Terasaki, I., Sasago, Y. & Uchinokura, K. Large thermoelectric power in NaCo2O4 single crystals. Phys. Rev. B 56, R12685–R12687 (1997)

    Article  ADS  CAS  Google Scholar 

  5. Loureiro, S. M. et al. Enhancement of metallic behaviour in bismuth cobaltates through lead doping. Phys. Rev. B 63, 094109-1–094109-9 (2001)

    Article  ADS  Google Scholar 

  6. Tsukada, I. et al. Ferromagnetism and large negative magnetoresistance in Pb doped Bi-Sr-Co-O misfit-layer compound. Preprint cond-mat/0012395 at 〈〉 (2000).

  7. Mihaly, G., Kezsmarki, I., Zambroszky, F. & Forro, L. Hall effect and conduction anisotropy in the organic conductor (TMTSF)2PF6 . Phys. Rev. Lett. 84, 2670–2673 (2000)

    Article  ADS  CAS  Google Scholar 

  8. Anderson, P. W. The Theory of Superconductivity in the High-Tc Cuprates (Princeton Univ. Press, Princeton, 1997)

    Google Scholar 

  9. Ioffe, L. B. & Millis, A. J. Zone-diagonal-dominated transport in high-TC cuprates. Phys. Rev. B 58, 11631–11637 (1998)

    Article  ADS  CAS  Google Scholar 

  10. Voit, J. One-dimensional Fermi liquids. Rep. Prog. Phys. 57, 977–1116 (1994)

    Google Scholar 

  11. Fisk, Z. et al. Heavy-electron metals: New highly correlated states of matter. Science 239, 33–42 (1988)

    Article  ADS  CAS  Google Scholar 

  12. Reinert, F. et al. Temperature dependence of the Kondo resonance and its satellites in CeCu2Si2 . Phys. Rev. Lett. 87, 106401-1–106401-4 (2001)

    Article  ADS  MathSciNet  Google Scholar 

  13. Pruschke, T., Cox, D. L. & Jarrell, H. Hubbard model at infinite dimensions: Thermodynamic and transport properties. Phys. Rev. B 47, 3553–3565 (1993)

    Article  ADS  CAS  Google Scholar 

  14. Georges, A., Kotliar, G., Krauth, W. & Rozenberg, M. J. Dynamical mean-field theory of strongly correlated fermion systems and the limit of infinite dimensions. Rev. Mod. Phys. 68, 13–125 (1996)

    Article  ADS  MathSciNet  CAS  Google Scholar 

  15. Merino, J. & McKenzie, R. H. Transport properties of strongly correlated metals: A dynamical mean-field approach. Phys. Rev. B 61, 7996–8008 (2000)

    Article  ADS  CAS  Google Scholar 

  16. Ioffe, A. F. & Regel, A. R. Non-crystalline, amorphous and liquid electronic semiconductors. Prog. Semicond. 4, 237–291 (1960)

    Google Scholar 

  17. Biermann, S., Georges, A., Lichenstein, A. & Gianmarchi, T. Deconfinement transition and Luttinger to Fermi liquid crossover in quasi one-dimensional systems. Preprint cond-mat/0107633 at 〈〉 (2001).

  18. Carlson, E. W., Orgad, D., Kivelson, S. A. & Emery, V. J. Dimensional crossover in quasi-one-dimensional and high-T C superconductors. Phys. Rev. B 62, 3422–3437 (2000)

    Article  ADS  CAS  Google Scholar 

  19. Valla, T. et al. Temperature dependent scattering rates at the Fermi surface of optimally doped Bi2Sr2CaCu2O8+δ . Phys. Rev. Lett. 85, 828–831 (2000)

    Article  ADS  CAS  Google Scholar 

  20. Valla, T. et al. Evidence for quantum critical behaviour in the optimally doped cuprate Bi2Sr2CaCu2O8+δ . Science 285, 2110–2113 (1999)

    Article  CAS  Google Scholar 

  21. Ding, H. et al. Spectroscopic evidence for a pseudogap in the normal state of underdoped high-Tc superconductors. Nature 382, 51–54 (1996)

    Article  ADS  CAS  Google Scholar 

  22. Watanabe, T., Fujii, T. & Matsuda, A. Pseudogap in Bi2Sr2CaCu2O8+δ studied by measuring anisotropic susceptibilities and out-of-plane transport. Phys. Rev. Lett. 84, 5849–5852 (2000)

    Article  ADS  Google Scholar 

  23. Yusof, Z. et al. Quasiparticle liquid in the highly overdoped Bi2Sr2CaCu2O8 + δ. Preprint cond-mat/0104367 at 〈〉 (2001).

  24. Lavrov, A. N., Kameneva, M. Y. & Kozeeva, L. P. Normal-state resistivity anisotropy in underdoped RBa2Cu3O6+x crystals. Phys. Rev. Lett. 81, 5636–5639 (1998)

    Article  ADS  CAS  Google Scholar 

Download references


We thank A. Tsvelik, R. Werner, S. A. Kivelson and A. V. Fedorov for discussions. The work at BNL and the National Synchrotron Light Source where the experiments were carried out was supported by the US Department of Energy. B.W. thanks the A.P. Sloan foundation for a Research Fellowship.

Author information

Authors and Affiliations


Corresponding author

Correspondence to T. Valla.

Ethics declarations

Competing interests

The authors declare that they have no competing financial interests.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Valla, T., Johnson, P., Yusof, Z. et al. Coherence–incoherence and dimensional crossover in layered strongly correlated metals. Nature 417, 627–630 (2002).

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI:

This article is cited by


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

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