AlkaliAtom.getTransitionRate(n1, l1, j1, n2, l2, j2, temperature=0.0, s=0.5)[source]#

Transition rate due to coupling to vacuum modes (black body included)

Calculates transition rate from the first given state to the second given state \(|n_1,l_1,j_1\rangle \rightarrow |n_2,j_2,j_2\rangle\) at given temperature due to interaction with the vacuum field. For zero temperature this returns Einstein A coefficient. For details of calculation see Ref. 1 and Ref. 2. See Black-body induced population transfer example snippet.

  • n1 (int) – principal quantum number

  • l1 (int) – orbital angular momentum

  • j1 (float) – total angular momentum

  • n2 (int) – principal quantum number

  • l2 (int) – orbital angular momentum

  • j2 (float) – total angular momentum

  • [temperature] (float) – temperature in K

  • s (float) – optional, total spin angular momentum of state. By default 0.5 for Alkali atoms.


transition rate in s \({}^{-1}\) (SI)

Return type




C. E. Theodosiou, PRA 30, 2881 (1984)


I. I. Beterov, I. I. Ryabtsev, D. B. Tretyakov, and V. M. Entin, PRA 79, 052504 (2009)