DISCOVERY OF TUNNELLING SUPERCURRENTS
DISCOVERY OF TUNNELLING SUPERCURRENTS
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DOI:
10.1103/revmodphys.46.251
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发表时间:
1974-01-01
影响因子:
44.1
通讯作者:
JOSEPHSON, BD
中科院分区:
文献类型:
--
作者:
JOSEPHSON, BD
The. events leading to the discovery of tunnelling supercurrents took place while I was working as a research student at the Royal Society Mond Laboratory, Cambridge, under the supervision of Professor Brian Pippard. Duringmy second year as a research student, in 1961—2, we werefortunate to have as a visitor to the laboratory Professor Phil Anderson, who has made numerous contributions to the subjectof tunnelling supercurrents, including a number of unpublished results derived independently of myself. His lecture course in Cambridge introduced the new concept of'broken sym-metry'in superconductors,(Anderson, 1963) which was already inherent in his 1958 pseudospin formulation of superconductivity theory (Anderson, 1958), which I shall now describe.As discussed by Cooper in his Nobel lecture last year (Cooper, 1973), according to the Bardeen—Cooper-Schrieffer theory there is a strong positive correlation in a superconductor between the occupation of two electron states of equal and opposite momentum and spin. Anderson showed that in the idealized case where the correla-tion is perfect, the system can be represented by a set of interacting'pseudospins,'with one pseudospin for each pair of electron states. The situation in which both states are unoccupied is represented by a pseudospin in the positive z direction, while occupationof both states is represented by a pseudospin in the negative z direction; other pseudospin orientations correspond to a superposition of the two possibilities.