Alfred Kastler was a French

French people

The French are a nation that share a common French culture and speak the French language as a mother tongue. Historically, the French population are descended from peoples of Celtic, Latin and Germanic origin, and are today a mixture of several ethnic groups...

 physicist

Physicist

A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

, and Nobel Prize laureate.

Kastler was born in Guebwiller

Guebwiller

Guebwiller is a commune in the Haut-Rhin department in Alsace in north-eastern France.It is situated northwest of Mulhouse at the foot of the Vosges mountains...

 (Alsace

Alsace

Alsace is the fifth-smallest of the 27 regions of France in land area , and the smallest in metropolitan France. It is also the seventh-most densely populated region in France and third most densely populated region in metropolitan France, with ca. 220 inhabitants per km²...

) and later attended the Lycée Bartholdi in Colmar, Alsace, and École Normale Supérieure

École Normale Supérieure

The École normale supérieure is one of the most prestigious French grandes écoles...

 in Paris in 1921. After his studies, in 1926 he began teaching physics

Physics

Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

 at the Lycée of Mulhouse

Mulhouse

Mulhouse |mill]] hamlet) is a city and commune in eastern France, close to the Swiss and German borders. With a population of 110,514 and 278,206 inhabitants in the metropolitan area in 2006, it is the largest city in the Haut-Rhin département, and the second largest in the Alsace region after...

, and then taught at the University of Bordeaux

University of Bordeaux

University of Bordeaux is an association of higher education institutions in and around Bordeaux, France. Its current incarnation was established 21 March 2007. The group is the largest system of higher education schools in southwestern France. It is part of the Academy of Bordeaux.There are seven...

, where he was a university professor until 1941. Georges Bruhat asked him to come back to the École Normale Supérieure, where he finally obtained a chair in 1952.

Collaborating with Jean Brossel, he researched quantum mechanics

Quantum mechanics

Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...

, the interaction between light

Light

Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

 and atom

Atom

The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...

s, and spectroscopy

Spectroscopy

Spectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative...

. Kastler, working on combination of optical resonance and magnetic resonance

Magnetic resonance

Magnetic resonance can mean:*Nuclear magnetic resonance*Electron spin resonance*Magnetic resonance imaging *Functional magnetic resonance imaging *Muon spin spectroscopy...

, developed the technique of "optical pumping

Optical pumping

Optical pumping is a process in which light is used to raise electrons from a lower energy level in an atom or molecule to a higher one. It is commonly used in laser construction, to pump the active laser medium so as to achieve population inversion...

". Those works led to the completion of the theory of laser

Laser

A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...

s and maser

Maser

A maser is a device that produces coherent electromagnetic waves through amplification by stimulated emission. Historically, “maser” derives from the original, upper-case acronym MASER, which stands for "Microwave Amplification by Stimulated Emission of Radiation"...

s.

He won the Nobel Prize in Physics

Nobel Prize in Physics

The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...

 in 1966 "for the discovery and development of optical methods for studying Hertzian resonances in atoms".

He was president of the board of the Institut d'optique théorique et appliquée.

Laboratoire Kastler-Brossel

Professor Kastler spent most of his research career at the Ecole Normale Supérieure in Paris where he started after the war with his student, Jean Brossel a small research group on spectroscopy.

Over the forty years that followed, this group has trained many of young physicists and had a significant impact on the development of the science of atomic physics

Atomic physics

Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. It is primarily concerned with the arrangement of electrons around the nucleus and...

 in France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

. The Laboratoire de Spectroscopie hertzienne has then been renamed Laboratoire Kastler-Brossel in 1994 and has got a part of its laboratory in Université Pierre et Marie Curie  mainly at the Ecole Normale Supérieure

École Normale Supérieure

The École normale supérieure is one of the most prestigious French grandes écoles...

.

Professor Kastler died on 7 January 1984, in Bandol

Bandol

Bandol is a commune in the Var department in the Provence-Alpes-Côte d'Azur region in southeastern France.-References:*...

, France.

External links

• Alfred Kastler biography at Timeline of Nobel Winners