Possible light-induced superconductivity in K3C60 at high temperature

  • Nature volume 530, pages 461464 (25 February 2016)
  • doi:10.1038/nature16522
  • Download Citation


The non-equilibrium control of emergent phenomena in solids is an important research frontier, encompassing effects such as the optical enhancement of superconductivity1. Nonlinear excitation2,3 of certain phonons in bilayer copper oxides was recently shown to induce superconducting-like optical properties at temperatures far greater than the superconducting transition temperature, Tc (refs 4, 5, 6). This effect was accompanied by the disruption of competing charge-density-wave correlations7,8, which explained some but not all of the experimental results. Here we report a similar phenomenon in a very different compound, K3C60. By exciting metallic K3C60 with mid-infrared optical pulses, we induce a large increase in carrier mobility, accompanied by the opening of a gap in the optical conductivity. These same signatures are observed at equilibrium when cooling metallic K3C60 below Tc (20 kelvin). Although optical techniques alone cannot unequivocally identify non-equilibrium high-temperature superconductivity, we propose this as a possible explanation of our results.

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Change history

  • Corrected online 24 February 2016

    The final sentence of the Fig. 4 legend was inadvertently truncated in the PDF of the AOP version, but has now been corrected.


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We acknowledge S. Kivelson and A. Georges for discussion. We are also grateful to A. Subedi for sharing microscopic calculations of anharmonic mode coupling. We thank L. Degiorgi for sharing optical data measured on single crystals. Technical support during sample handling was provided by H.-P. Liermann and M. Wendt. We additionally acknowledge support from M. Gaboardi (for SQUID magnetometry) and from J. Harms (for graphics). The research leading to these results received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013)/ERC Grant Agreement no. 319286 (QMAC). We acknowledge support from the Deutsche Forschungsgemeinschaft via the excellence cluster ‘The Hamburg Centre for Ultrafast Imaging — Structure, Dynamics and Control of Matter at the Atomic Scale’ and the priority program SFB925. This work was also supported by the Swiss National Supercomputing Center (CSCS) under the project ID s497.

Author information


  1. Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany

    • M. Mitrano
    • , A. Cantaluppi
    • , D. Nicoletti
    • , S. Kaiser
    • , S. R. Clark
    •  & A. Cavalleri
  2. The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany

    • A. Cantaluppi
    • , D. Nicoletti
    •  & A. Cavalleri
  3. INSTM UdR Trieste-ST and Elettra–Sincrotrone Trieste S.C.p.A., Area Science Park, 34012 Basovizza, Trieste, Italy

    • A. Perucchi
    •  & P. Di Pietro
  4. CNR-IOM and Dipartimento di Fisica, Università di Roma “Sapienza”, Piazzale A. Moro 2, 00185 Roma, Italy

    • S. Lupi
  5. Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Parma, Parco Area delle Scienze, 7/a, 43124 Parma, Italy

    • D. Pontiroli
    •  & M. Riccò
  6. Department of Physics, University of Bath, Claverton Down, Bath BA2 7AY, UK

    • S. R. Clark
  7. Department of Physics, Oxford University, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, UK

    • S. R. Clark
    • , D. Jaksch
    •  & A. Cavalleri
  8. Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543, Singapore

    • D. Jaksch


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A. Cavalleri conceived the project and the experiments together with M.M. and S.K. The time-resolved THz set-up was built by M.M. and A. Cantaluppi, who performed the pump–probe measurements and analysed the data with support from D.N. and S.K. Equilibrium optical properties were measured and analysed by M.M. and A. Cantaluppi, with support from A.P., S.L. and P.D.P. Samples were grown and characterized by D.P. and M.R. S.R.C. and D.J. provided calculations of time-dependent on-site correlation energies. The manuscript was written by A. Cavalleri, D.N. and M.M., with input from all authors.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to A. Cavalleri.

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