Editing Josephson effect (section)

==History==
[[File:Mond building, Cambridge.jpg|thumb|right|Mond Laboratory building<ref name=Mond>[https://historicengland.org.uk/listing/the-list/list-entry/1268374?section=official-list-entry Mond Laboratory], National Heritage List for England, Historic England (accessed 17 September 2022)</ref>]]
The DC Josephson effect had been seen in experiments prior to 1962,<ref>{{Cite web |last=Josephson |first=Brian D. |date=December 12, 1973 |title=The Discovery of Tunneling Supercurrents (Nobel Lecture) |url=https://www.nobelprize.org/prizes/physics/1973/josephson/lecture/}}</ref> but had been attributed to "super-shorts" or breaches in the insulating barrier leading to the direct conduction of electrons between the superconductors.

In 1962, Brian Josephson became interested in superconducting tunneling. He was then 23 years old and a second-year graduate student of [[Brian Pippard]] at the [[New Museums Site#Mond Laboratory|Mond Laboratory]] of the [[University of Cambridge]]. That year, Josephson took a many-body theory course with [[Philip W. Anderson]], a [[Bell Labs]] employee on sabbatical leave for the 1961–1962 academic year. The course introduced 
Josephson to the idea of broken symmetry in superconductors, and he "was fascinated by the idea of broken symmetry, and wondered whether there could be any way of observing it experimentally". Josephson studied the experiments by [[Ivar Giaever]] and Hans Meissner, and theoretical work by Robert Parmenter. Pippard initially believed that the tunneling effect was possible but that it would be too small to be noticeable, but Josephson did not agree, especially after Anderson introduced him to a preprint of "Superconductive Tunneling" by [[Marvin L. Cohen|Cohen]], [[Leopoldo Máximo Falicov|Falicov]], and Phillips about the superconductor-barrier-normal metal system.<ref>{{cite journal |title=Superconductive Tunneling |first1=M. H. |last1=Cohen |first2=L. M. |last2=Falicov |first3=J. C. |last3=Phillips |date=15 April 1962 |journal=Physical Review Letters |volume=8 |issue=8 |pages=316–318 |doi=10.1103/PhysRevLett.8.316 |bibcode=1962PhRvL...8..316C |url=https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.8.316|url-access=subscription }}</ref>{{r|trueGenius|pp=223-224}}

Josephson and his colleagues were initially unsure about the validity of Josephson's calculations. Anderson later remembered:
<blockquote>
We were all—Josephson, Pippard and myself, as well as various other people who also habitually sat at the [[New Museums Site#Mond Laboratory|Mond]] tea and participated in the discussions of the next few weeks—very much puzzled by the meaning of the fact that the current depends on the phase.
</blockquote>
After further review, they concluded that Josephson's results were valid. Josephson then submitted "Possible new effects in superconductive tunnelling" to ''[[Physics Letters]]'' in June 1962{{r|possibleNewEffects}}. The newer journal ''Physics Letters'' was chosen instead of the better established ''[[Physical Review Letters]]'' due to their uncertainty about the results. [[John Bardeen]], by then already Nobel Prize winner, was initially publicly skeptical of Josephson's theory in 1962, but came to accept it after further experiments and theoretical clarifications.<ref name="trueGenius">{{cite book |url=https://archive.org/details/truegeniuslifesc0000hodd |url-access=registration |title=True Genius: The Life and Science of John Bardeen |publisher=Joseph Henry Press |page=[https://archive.org/details/truegeniuslifesc0000hodd/page/117 117] |isbn=9780309084086 |last1=Daitch |first1=Vicki |last2=Hoddeson |first2=Lillian |year= 2002 }}</ref>{{rp|pp=222–227}} See also: {{section link|John Bardeen|Josephson effect controversy}}.

In January 1963, Anderson and his [[Bell Labs]] colleague John Rowell submitted the first paper to ''Physical Review Letters'' to claim the experimental observation of Josephson's effect "Probable Observation of the Josephson Superconducting Tunneling Effect".<ref>{{cite journal |last1=Anderson |first1=P. W. |last2=Rowell |first2=J. M. |date=15 March 1963 |title=Probable Observation of the Josephson Tunnel Effect |url=https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.10.230 |journal=Physical Review Letters |volume=10 |issue=6 |pages=230 |bibcode=1963PhRvL..10..230A |doi=10.1103/PhysRevLett.10.230|url-access=subscription }} 
<!--|access-date=16 May 2012--></ref> These authors were awarded patents<ref>{{Cite patent|number=US3335363A|title=Superconductive device of varying dimension having a minimum dimension intermediate its electrodes|gdate=1967-08-08|invent1=Anderson|invent2=Dayem|inventor1-first=Philip W.|inventor2-first=Aly H.|url=https://patents.google.com/patent/US3335363A/en}}</ref> on the effects that were never enforced, but never challenged.{{Citation needed|date=March 2023}}

Before Josephson's prediction, it was only known that single (i.e., non-paired) electrons can flow through an insulating barrier, by means of [[quantum tunneling]]. Josephson was the first to predict the tunneling of superconducting [[Cooper pair]]s. For this work, Josephson received the [[Nobel Prize in Physics]] in 1973.<ref>{{Cite web |title=The Nobel Prize in Physics 1973 |url=https://www.nobelprize.org/prizes/physics/1973/summary/ |access-date=2023-03-01 |website=The Nobel Prize}}</ref> John Bardeen was one of the nominators.{{r|trueGenius|p=230}}