Understanding the Path from Classical to Quantum Mechanics by Jaroslav Zamastil

Author:Jaroslav Zamastil
Language: eng
Format: epub, pdf
ISBN: 9783031373732
Publisher: Springer Nature Switzerland

(4.6)

The number of the atoms at the state n increases if the atom in the state k absorbs radiation and decreases if the atom in the state n undergoes stimulated or spontaneous emission to the state k, so

(4.7)

where , , and are coefficients of the absorption, stimulated and spontaneous emission, respectively. Let us first note that in the absence of radiation

(4.8)

so the coefficient expresses the probability per unit time that the atom in the state n spontaneously emits EM radiation and goes to the state k. Likewise, the coefficient expresses the probability per unit time per energy density that the atom in the state k absorbs radiation of energy density and goes to the state n. Now, at thermal equilibrium, the number of atoms at the state n first does not change in time, and second, it is related to the number of atoms at the state k according to canonical distribution, cf. Eq. (4.6),

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.