TY - JOUR
T1 - Superfluid 3He-the early days
AU - Lee, D. M.
AU - Leggett, A. J.
N1 - Funding Information:
Acknowledgements A.J.L. would like to acknowledge the support of the National Science Foundation under award No. NSF-DMR-09-06921. D.M.L. thanks the Norman Hackerman Advanced Research Program of the State of Texas for their support of this project under grant No. 010366-0137-2009 during the preparation of this manuscript.
PY - 2011/8
Y1 - 2011/8
N2 - A history is given of liquid 3He research from the time when 3He first became available following World War II through 1972 when the discovery of the superfluid phases was made. The Fermi liquid nature was established early on, and the Landau Fermi liquid theory provided a framework for understanding the interactions between the Fermions (quasiparticles). The theory's main triumph was to predict zero sound, which was soon discovered experimentally. Experimental techniques are treated, including adiabatic demagnetization, dilution refrigerator technology, and Pomeranchuk cooling. A description of the superfluid 3He discovery experiments using the latter two of these techniques is given. While existing theories provided a basis for understanding the newly discovered superfluid phases in terms of ℓ > 0 Cooper pairs, the unexpected stability of the A phase in the high-P, high-T region of the phase diagram needed for its explanation a creative leap beyond the BCS paradigm. The use of sum rules to interpret some of the unusual magnetic resonance in liquid 3He is discussed. Eventually a complete theory of the spin dynamics of superfluid 3He was developed, which predicted many of the exciting phenomena subsequently discovered.
AB - A history is given of liquid 3He research from the time when 3He first became available following World War II through 1972 when the discovery of the superfluid phases was made. The Fermi liquid nature was established early on, and the Landau Fermi liquid theory provided a framework for understanding the interactions between the Fermions (quasiparticles). The theory's main triumph was to predict zero sound, which was soon discovered experimentally. Experimental techniques are treated, including adiabatic demagnetization, dilution refrigerator technology, and Pomeranchuk cooling. A description of the superfluid 3He discovery experiments using the latter two of these techniques is given. While existing theories provided a basis for understanding the newly discovered superfluid phases in terms of ℓ > 0 Cooper pairs, the unexpected stability of the A phase in the high-P, high-T region of the phase diagram needed for its explanation a creative leap beyond the BCS paradigm. The use of sum rules to interpret some of the unusual magnetic resonance in liquid 3He is discussed. Eventually a complete theory of the spin dynamics of superfluid 3He was developed, which predicted many of the exciting phenomena subsequently discovered.
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U2 - 10.1007/s10909-011-0375-8
DO - 10.1007/s10909-011-0375-8
M3 - Review article
AN - SCOPUS:80052574730
SN - 0022-2291
VL - 164
SP - 140
EP - 172
JO - Journal of Low Temperature Physics
JF - Journal of Low Temperature Physics
IS - 3-4
ER -