Abstract
RECENT experiments on the inelastic scattering of neutrons by superfluid helium1,2 have given a direct confirmation of the correctness of the elementary excitation spectrum (rotons and phonons) of Landau's theory3. As it is usually formulated, the theory postulates that the excitation spectrum is independent of temperature. However, the velocity of sound is known to vary somewhat with temperature4, and the neutron scattering experiments1 show an appreciable fall in the minimum roton energy Δ, as the temperature approaches the λ-point.
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Larsson, K.-E., and Otnes, K., Kamerlingh Onnes Conference, Physica, 24, S145 (1958); Arkiv för Fysik, 15, 49 (1959).
Yarnell, J. L., Arnold, G. P., Bendt, P. J., and Kerr, F. C., Phys. Rev. Letters, 1, 9 (1958); Kamerlingh Onnes Conference, Physica, 24, S146 (1958).
Landau, L. D., J. Phys. (Moscow), 5, 71 (1941); 11, 91 (1947). Feynman, R. P., and Cohen, M., Phys. Rev., 102, 1189 (1956); 107, 13 (1957).
Atkins, K. R., and Chase, C. E., Proc. Phys. Soc., A, 64, 826 (1951).
Valatin, J. G., and Butler, D., Nuovo Cim., 10, 37 (1958). Compare the situation in the theory of superconductivity, Bardeen, J., Cooper, L. N., and Schrieffer, J. R., Phys. Rev., 108, 1175 (1957).
Ehrenfest, P., Proc. Kon. Acad. Wet., Amsterdam (Science Section), 36, 153 (1933).
Fairbank, W. M., Buckingham, M. J., and Kellers, C. F., Proc. Fifth Internat. Conf. on Low Temperature Physics and Chemistry, Madison, Wis., 50 (1958).
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KUPER, C. The λ-Transition in Helium. Nature 183, 1544–1545 (1959). https://doi.org/10.1038/1831544b0
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DOI: https://doi.org/10.1038/1831544b0
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