spontaneous emission
Quick Summary
Spontaneous emission is a fundamental process in quantum mechanics where an atom in an excited, high-energy state releases a photon and transitions to a lower energy state. This emission is a probabilistic event, with the average time for this transition typically ranging from 10-9 to 10-8 seconds.1
This process is distinct from stimulated emission, where an incoming photon triggers an excited atom to release an identical photon. Spontaneous emission occurs without external intervention and is a key mechanism for how atoms lose excess energy. The probability of spontaneous emission is determined by the atom's specific energy states and the nature of the transition.2314
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- radiationAbsorption and emission
…multiplied by the probability of spontaneous emission, Aji, to the ground state plus the additional induced emission term, Nj Bji I(ν), in which Bji is a term that Einstein showed to be equal to Bi
Read More…multiplied by the probability of spontaneous emission, Aji, to the ground state plus the additional induced emission term, Nj Bji I(ν), in which Bji is a term that Einstein showed to be equal to Bi
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lightSpontaneous emissionWhen an isolated atom is excited into a high-energy state, it generally remains in the excited state for a short time before emitting a photon and making a transition to a lower energy state. This fundamental process is called spontaneous emission. The emission…
Read MoreWhen an isolated atom is excited into a high-energy state, it generally remains in the excited state for a short time before emitting a photon and making a transition to a lower energy state. This fundamental process is called spontaneous emission. The emission…
Read More