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Probable heat capacity signature of the supersolid transition

Abstract

Liquid 4He enters the superfluid state and flows without friction below 2.176 K. Thin liquid films adsorbed on solid substrates undergo the same transformation, although at a lower temperature. When the substrate is subjected to oscillatory motion a portion of the film, known as the superfluid fraction, decouples from the oscillation. A similar phenomenon has been observed1,2 in solid 4He, in which a fraction of the solid seems to decouple from the motion of the surrounding lattice. Although this observation has been replicated in various laboratories3,4,5,6, no thermodynamic signature of the possible supersolid transition has been seen. Here we report the finding of a heat capacity peak that coincides with the onset of mass decoupling. This complementary experimental evidence supports the existence of a genuine transition between the normal solid and supersolid phases of 4He.

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Figure 1: Heat capacity of four samples containing different amounts of 3 He impurities.
Figure 2: Plot of Cn/T against T2 for x3 = 1 p.p.b., 0.3 p.p.m., 10 p.p.m. and 30 p.p.m.
Figure 3: Plot of specific heat against T3.
Figure 4: Specific heat peaks of the 1 p.p.b., 0.3 p.p.m. and 10 p.p.m. samples.

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References

  1. Kim, E. & Chan, M. H. W. Probable observation of a supersolid helium phase. Nature 427, 225–227 (2004)

    Article  CAS  ADS  Google Scholar 

  2. Kim, E. & Chan, M. H. W. Observation of superflow in solid helium. Science 305, 1941–1944 (2004)

    Article  CAS  ADS  Google Scholar 

  3. Rittner, A. S. C. & Reppy, J. D. Observation of classical rotational inertia and nonclassical supersolid signals in solid 4He below 250 mK. Phys. Rev. Lett. 97, 165301 (2006)

    Article  ADS  Google Scholar 

  4. Kondo, M., Takada, S., Shibayama, Y. & Shirahama, K. Observation of non-classical rotational inertia in bulk solid 4He. J. Low Temp. Phys. 148, 695–699 (2007)

    Article  CAS  ADS  Google Scholar 

  5. Penzev, A., Yasuta, Y. & Kubota, M. Annealing effect for supersolid fraction in 4He. J. Low Temp. Phys. 148, 677–681 (2007)

    Article  CAS  ADS  Google Scholar 

  6. Aoki, Y., Graves, J. C. & Kojima, H. Oscillation frequency dependence of nonclassical rotation inertia of solid 4He. Phys. Rev. Lett. 99, 015301 (2007)

    Article  CAS  ADS  Google Scholar 

  7. Leggett, A. J. Can a solid be ‘superfluid’? Phys. Rev. Lett. 25, 1543–1546 (1970)

    Article  CAS  ADS  Google Scholar 

  8. Rittner, A. S. C. & Reppy, J. D. Disorder and the supersolid state of solid 4He. Phys. Rev. Lett. 98, 175302 (2007)

    Article  ADS  Google Scholar 

  9. Prokof’ev, N. V. What makes a crystal supersolid? Adv. Phys. 56, 381–402 (2007)

    Article  ADS  Google Scholar 

  10. Clark, A. C., West, J. T. & Chan, M. H. W. Nonclassical rotational inertia in helium crystal. Phys. Rev. Lett. 99, 135302 (2007)

    Article  CAS  ADS  Google Scholar 

  11. Anderson, P. W. Two new vortex liquids. Nature Phys. 3, 160–162 (2007)

    Article  CAS  ADS  Google Scholar 

  12. Heltemes, E. C. & Swenson, C. A. Heat capacity of solid 3He. Phys. Rev. 128, 1512–1519 (1962)

    Article  CAS  ADS  Google Scholar 

  13. Edwards, D. O. & Pandorf, R. C. Heat capacity and other properties of hexagonal close-packed helium-4. Phys. Rev. 140, A816–A825 (1965)

    Article  ADS  Google Scholar 

  14. Gardner, W. R., Hoffer, J. K. & Phillips, N. E. Thermodynamic properties of 4He. The hcp phase at low densities. Phys. Rev. A. 7, 1029–1043 (1973)

    Article  CAS  ADS  Google Scholar 

  15. Castles, S. H. & Adams, E. D. Specific heat of solid helium. J. Low Temp. Phys. 19, 397–431 (1975)

    Article  CAS  ADS  Google Scholar 

  16. Hébral, B., Frossati, G., Godfrin, H., Thoulouze, D., Greenberg, A. S. & in Phonons in Condensed Matter (ed. Maris, H. J.) 169–172 (Plenum, New York, 1980)

    Book  Google Scholar 

  17. Clark, A. C. & Chan, M. H. W. Specific heat of solid helium. J. Low Temp. Phys. 138, 853–858 (2005)

    Article  CAS  ADS  Google Scholar 

  18. Sullivan, P. F. & Seidel, G. Steady-state, ac-temperature calorimetry. Phys. Rev. 173, 679–685 (1968)

    Article  CAS  ADS  Google Scholar 

  19. Nussinov, Z., Balatsky, A. V., Graf, M. J. & Trugman, S. A. Origin of the decrease in the torsional-oscillator period of solid 4He. Phys. Rev. B 76, 014530 (2007)

    Article  ADS  Google Scholar 

  20. Grigorev, V. N. et al. Observation of a glassy phase in solid 4He in the supersolidity region. Preprint at 〈http://arxiv.org/abs/cond-mat/0702133〉 (2007)

  21. Richards, M. G., Pope, J. & Widom, A. Evidence for isotopic impuritons in solid helium. Phys. Rev. Lett. 29, 708–711 (1972)

    Article  CAS  ADS  Google Scholar 

  22. Grigor’ev, V. N. et al. 3He impurity excitations in solid 4He. J. Low Temp. Phys. 13, 65–79 (1973)

    Article  ADS  Google Scholar 

  23. Allen, A. R., Richards, M. G. & Schratter, J. Anomalous temperature dependence of D and T 2 for dilute solutions of 3He in solid 4He. J. Low Temp. Phys. 47, 289–320 (1982)

    Article  CAS  ADS  Google Scholar 

  24. Hébral, B. et al. Fermi-liquid droplets in liquid-solid solutions of the helium isotopes. Phys. Rev. Lett. 46, 42–45 (1981)

    Article  ADS  Google Scholar 

  25. Schrenk, R., Friz, O., Fujii, Y., Syskakis, E. & Pobell, F. Heat capacity and pressure at phase separation and solidification of 3He in hcp 4He. J. Low Temp. Phys. 84, 133–156 (1991)

    Article  CAS  ADS  Google Scholar 

  26. Todoshchenko, I. A. et al. Melting curve of 4He: no sign of a supersolid transition down to 10 mK. Phys. Rev. Lett. 97, 165302 (2006)

    Article  CAS  ADS  Google Scholar 

  27. Todoshchenko, I. A., Alles, H., Junes, H. J., Parshin, A., Ya & Tsepelin, V. Absence of low temperature anomaly on the melting curve of 4He. JETP Lett. 85, 555–558 (2007)

    Article  Google Scholar 

  28. Singsaas, A. & Ahlers, G. Universality of static properties near the superfluid transition in 4He. Phys. Rev. B 30, 5103–5115 (1984)

    Article  CAS  ADS  Google Scholar 

  29. Yoon, J. & Chan, M. H. W. Superfluid transition of 4He in porous gold. Phys. Rev. Lett. 78, 4801–4804 (1997)

    Article  CAS  ADS  Google Scholar 

  30. Zassenhaus, G. M. & Reppy, J. D. Lambda point in the 4He-Vycor system: a test of hyperuniversality. Phys. Rev. Lett. 83, 4800–4803 (1999)

    Article  CAS  ADS  Google Scholar 

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Acknowledgements

We thank J. A. Lipa for the 1 p.p.b. purity helium, and J. Jain, J. S. Kurtz and N. Mulders for their advice. Funding was provided by the National Science Foundation.

Author Contributions X.L., A.C.C. and M.H.W.C. contributed equally to this work.

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Correspondence to M. H. W. Chan.

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Supplementary information

Supplementary Information

The file contains Supplementary Figure and Legend and Supplementary Discussion. The figure shows the temperature dependence of the specific heat of the four samples with the constant specific heat term of the 10 ppm and 30 ppm samples, deduced from Fig.3, subtracted. We further discuss: 1) Previous heat capacity measurements below 200 mK; 2) Accuracy and uncertainty in the 3He concentration of the samples studied; 3) High temperature deviation from the Debye specific heat; 4) Additional comments on the constant specific heat term found for the 10 ppm and 30 ppm samples; 5) Evidence against phase separation as the origin of the 75 mK peak. (PDF 153 kb)

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Lin, X., Clark, A. & Chan, M. Probable heat capacity signature of the supersolid transition. Nature 449, 1025–1028 (2007). https://doi.org/10.1038/nature06228

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