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A physicist living in Brazil co-authored the experiments that led a Frenchman to win a Nobel prize

Physicist Mario Norberto Baibich, an Argentinian living in Brazil and a professor at the Federal University of Rio Grande do Sul (UFRGS), was the main author of the pioneering article, published in 1988 in the journal Physical Review Letters, whose discoveries and  resulting developments led the Nobel Physics Prize to be won by Frenchman Albert Fert. Working in Fert’s laboratory in France, at the University of Paris-South, Baibich carried out an experiment that discovered the existence of a phenomenon called giant magnetoresistance, which would pave the way for the miniaturization of hard disks and the popularization of microcomputers. German Peter Grünberg, who shared the prize with Fert, had proposed the phenomenon in 1986.

Measuring magnetoresistance in samples of chromium and iron was done jointly by Baibich and Fert, who also signed the pioneering article. “They were doing tests in the laboratory with multilayers of magnetic and nonmagnetic material and, encouraged by Fert, I became interested in measuring the magnetoresistance of these layers”, recalls Baibich. He identified the potential of the magnetic multilayer by using 40 minute piled-up iron plates, a magnetic material, and non-magnetic chrome. He then noticed that the material he had chosen and the distribution of the parallel and alternate layers, when submitted to a magnetic field, reduced the resistance to electrical currents by as much as 100%, a reduction which previously had not even reached  5%.

“I showed the results to Fert and in just one night he came up with the idea of how to explain this phenomenon. He developed the model and asked the right questions”, explains the physicist from UFRGS, who harbors no harsh feeling for not sharing the Nobel prize with the Frenchman and the German. “The prize is not just for the discovery; it’s for everything that went on around it to carry this discovery forward. They deserve it more than I do, because they kept on with this line of research and drove the thing forward.” When he returned to Brazil, Baibich continued his research (to this day he is still investigating magnetoresistance) but not at the speed he was aiming at. “There was no equipment for making the nanometric films and people thought I wanted very expensive things. People were always reticent about my requests for help. Things got harder than they were when I was in France.”

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