L11.2 Transition rates for stimulated emission and absorption processes
20:55
L11.3 Ionization of hydrogen: conditions of validity, initial and final states
26:34
L9.1 The interaction picture and time evolution
15:13
L11.1 Harmonic transitions between discrete states
22:56
L1.1 General problem. Non-degenerate perturbation theory
42:51
Amplication by Stimulated Emission
20:32
L10.1 Box regularization: density of states for the continuum
19:32
L12.3 Einstein's argument: the need for spontaneous emission
20:56