Thursday, November 28, 2019

1987 Nobel Prize in Physics

1987 Nobel Prize in Physics The 1987 Nobel Prize in Physics went to German physicist J. Georg Bednorz and Swiss physicist K. Alexander Muller for discovery that certain classes of ceramics could be designed that had effectively no electrical resistance, meaning that there were ceramic materials that could be used as superconductors. The key aspect of these ceramics is that they represented the first class of high-temperature superconductors and their discovery had groundbreaking effects on the types of materials that could be used within sophisticated electronic devices Or, in the words of the official Nobel Prize announcement, the two researchers received the award for their important breakthrough in the discovery of superconductivity in ceramic materials. The Science These physicists were not the first to discover superconductivity, which had been identified in 1911 by Kamerlingh Onnes while researching mercury. Essentially, as mercury was reduced in temperature, there was a point at which it seemed to lose all electrical resistance, meaning that electrical current count flow through it unimpeded, creating a supercurrent. This is what it means to be a superconductor. However, the mercury only exhibited the superconducting properties at very low degrees near absolute zero, around 4 degrees Kelvin. Later research in the 1970s did identify materials that exhibited superconducting properties at around 13 degrees Kelvin. Bednorz and Muller were working together to research the conductive properties of ceramics at an IBM research laboratory near Zurich, Switzerland, in 1986, when they discovered the superconducting properties in these ceramics at temperatures of approximately 35 degrees Kelvin. The material used by Bednorz and Muller was a compound of lanthanum and copper oxide that was doped with barium. These high-temperature superconductors were confirmed very quickly by other researchers, and they were awarded the Nobel Prize in Physics the following year. All of the high-temperature superconductors are known as a Type II superconductor, and one of the effects of this is that when they have a strong magnetic field applied, they will exhibit only a partial  Meissner effect  that breaks down in a high magnetic field, because at a certain intensity of magnetic field the superconductivity of the material is destroyed by electrical vortices that form within the material. J. Georg Bednorz Johannes Georg Bednorz was born on May 16, 1950, in Neuenkirchen, in North-Rhine Westphalia in the Federal Republic of Germany (known to those of us in America as West Germany). His family had been displaced and split up during World War II, but they had reunited in 1949 and he was a late addition to the family. He attended the University of Munster in 1968, initially studying chemistry and then transitioning into the field of mineralogy, specifically crystallography, finding the mix of chemistry and physics more to his liking. He worked at the IBM Zurich Research Laboratory during the summer of 1972, which is when he first began working with Dr. Muller, head of the physics department. He began work on his Ph.D. in 1977 at the Swiss Federal Institute of Technology, in Zurich, with supervisors Prof. Heini Granicher and Alex Muller. He officially joined the staff of IBM in 1982, a decade after he spent the summer working there as a student. He began working on the search for a high-temperature superconductor with Dr. Muller in 1983, and they successfully identified their goal in 1986. K. Alexander Muller Karl Alexander Muller was born April 20, 1927, in Basel, Switzerland. He spent World War II in Schiers, Switzerland, attending the Evangelical College, completing his baccalaureate degree in seven years, starting at age 11 when his mother died. He followed this up with military training in the Swiss army and then transitioned to Zurichs Swiss Federal Institute of Technology. Among his professors was renowned physicist Wolfgang Pauli. He graduated in 1958, working then at the Battelle Memorial Institute in Geneva, then a Lecturer at the University of Zurich, and then finally landing a job at the IBM Zurich Research Laboratory in 1963. He conducted a range of research there, including serving as a mentor to Dr. Bednorz and collaborating together on the research to discover high-temperature superconductors, which resulted in the awarding of this Nobel Prize in Physics.

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