Леон Бриллюэн: Француз физигінің өмірі мен ғылыми еңбектері

French physicist

Léon Nicolas Brillouin (leɔ̃ nikɔla bʁijwɛ̃; August 7, 1889 – October 4, 1969) was a French physicist. He made contributions to quantum mechanics, radio wave propagation in the atmosphere, solid state physics, and information theory.

Brillouin was born in Sèvres, near Paris, France. His father, Marcel Brillouin, grandfather, Éleuthère Mascart, and great grandfather, Charles Briot, were physicists as well.

From 1908 to 1912, Brillouin studied physics at the École Normale Supérieure, in Paris. From 1911 he studied under Jean Perrin until he left for the Ludwig Maximilian University of Munich (LMU), in 1912. At LMU, he studied theoretical physics with Arnold Sommerfeld. Just a few months before Brillouin's arrival at LMU, Max von Laue had conducted his experiment showing X ray diffraction in a crystal lattice. In 1913, he went back to France to study at the University of Paris and it was in this year that Niels Bohr submitted his first paper on the Bohr model of the hydrogen atom. From 1914 until 1919, during World War I, he served in the military, developing the valve amplifier with G. A. Beauvais. At the conclusion of the war, he returned to the University of Paris to continue his studies with Paul Langevin, and was awarded his Docteur ès science in 1920. Brillouin's thesis jury was composed of Langevin, Marie Curie, and Jean Perrin and his thesis topic was on the quantum theory of solids. In his thesis, he proposed an equation of state based on the atomic vibrations (phonons) that propagate through it. He also studied the propagation of monochromatic light waves and their interaction with acoustic waves, i. e., scattering of light with a frequency change, which became known as Brillouin scattering.