In 1961, William Fairbank and Bascomb Deaver experimentally verified that magnetic flux can be quantized. This week I read an excellent paper on the history of the experiment. For those who aren't close to a library with access to the journal, (and for my own notes), here are a few of the highlights. For more info on the Fairbank/Deaver experiment see .
The Other Experiment
The Theory Connection
Nina Byers and Chen Yang, (of Yang-Mills fame), were working down the hall from Deaver and Fairbank while they were working on their experiment. The two theorists studied the results of the experiment and wrote up the theoretical explanation in an article that immediately followed Deaver and Fairbank article in PRL. When Fairbank showed preliminary data of the quantized flux plateaus to Chen he thought the data set was jut linear in the manner that might be expected if flux wasn't quantized. Fairbank explained to him that having taken the data he felt the experimenter could attach a sort of personality to each data point and almost subconsciously analyze the validity of each point. The completed data set at the end of the experiment bore out Fairbank's initial impressions. Byers and Yang are pictured below (picture 2).
The Cooper Pairs
Einzel D. (2011). 50 Years of Fluxoid Quantization: 2e or Not 2e, Journal of Low Temperature Physics, 163 (5-6) 215-237. DOI: 10.1007/s10909-011-0349-x
Doll R. & Näbauer M. (1961). Experimental Proof of Magnetic Flux Quantization in a Superconducting Ring, Physical Review Letters, 7 (2) 51-52. DOI: 10.1103/PhysRevLett.7.51
Byers N. & Yang C. (1961). Theoretical Considerations Concerning Quantized Magnetic Flux in Superconducting Cylinders, Physical Review Letters, 7 (2) 46-49. DOI: 10.1103/PhysRevLett.7.46