Stimulated emission of radiation
Emisión estimulada de radiación
- Date
- 1917 · confidence high
- Place
- Berlin, Germany
- Credited to
- Albert Einstein
- People
- 👤 Albert Einstein1879–1955
- Field
- Communication
What was discovered
While re-deriving Planck's law, Einstein discovers that a photon can induce an excited atom to emit another identical photon. It is the physical principle of the maser and the laser, realised four decades later.
'Zur Quantentheorie der Strahlung' (1917); in the same paper he introduces the momentum of the photon.
What it led to
- Maser (1954) and laser (1960)
- Einstein's A and B coefficients and radiation physics
- Quantum optics
Built on
- Planck's law of black-body radiation and the quantum of action1900
- Bohr model of the atom1913
- Planck's law
- Bohr model
- Boltzmann statistics
Made possible
- Maser1954
- The laser (and maser)1960
- Fibre-optic amplifiers