Superfluid transition in superfluid 3He in radially compressed aerogel
نویسندگان
چکیده
The Spin Supercurrent and Bose-Einstein condensation of magnons similar to an atomic BEC was observed in 1984 in superfluid He-B. Recently we discovered 2 new types of BEC in superfluid He in deformed aerogel. The orbital part of the wave function orients along the deformation and changes the magnon-magnon interaction. In some cases it forms a magnon trap. We can do it for He-A by uniaxially compressing the aerogel along the magnetic field . The other BEC state was observed in He-B in aerogel stretched along the magnetic field . Both states show all properties of magnon BEC. We have also observed a splitting of NMR lines near Tc, which seems to indicate the formation of a new phase of superfluid He in aerogel. The latter looks like an analog of the He-A1 phase with strongly enhanced magnetic field.
منابع مشابه
Quantum Phase Transition of 3He in Aerogel at a Nonzero Pressure
K. Matsumoto,* J. V. Porto, L. Pollack, E. N. Smith, T. L. Ho, and J. M. Parpia Laboratory of Atomic & Solid State Physics and Materials Science Center, Cornell University, Ithaca, New York 14853 (Received 14 January 1997) We present evidence for a nonzero pressure, T 0 superfluid phase transition of 3He in 98.2% open aerogel. Unlike bulk 3He which is a superfluid at T 0 at all pressures (d...
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