Curie, Pierre

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Curie, Pierre (1859-1906), French physicist and Nobel laureate, best known for the work on radioactivity that he did with his wife, Marie Curie. In radioactive materials the atoms break down spontaneously, releasing radiation in the form of energy and subatomic particles. Pierre Curie also worked on important topics in the structure of crystals and helped discover the piezoelectric effect in crystals—a property of producing electrical voltages when they are compressed.

Pierre Curie was born in Paris and educated at home by his parents. He studied physics at the University of Paris, earning a bachelor’s degree in 1875. He became an assistant teacher at the University of Paris in 1878 and turned his research to crystallography. In 1880 Pierre and his brother Jacques Curie discovered that some crystals developed positive electrical charges at one end and negative electrical charges at the other when the crystals were compressed. These crystals also change shape when exposed to electric voltage. The Curies called this effect the piezoelectric effect.

In 1894 Pierre Curie and Marie Sklodowska were introduced to one another. Their mutual devotion to scientific study led to their marriage in 1895. The same year, Pierre earned a doctoral degree in physics from the University of Paris for his research on magnetism. He showed that magnetic materials made of iron compounds lose their magnetic properties if heated beyond a certain temperature. This temperature, different for every material, is now called the Curie point. Until the mid-1890s most of Curie’s research was on magnetism and on crystals.

From 1895 on, the Curies worked on radioactivity. In 1898 they isolated the element radium from pitchblende, a radioactive mineral (mineral whose atoms spontaneously emit energy and subatomic particles) that also contains uranium. They shared the 1903 Nobel Prize in physics with French physicist Antoine Henri Becquerel for their work on radioactivity. Pierre became a professor of physics at the University of Paris in 1904.

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