Fermi's golden rule

Fermi's golden rule is valid when the initial state has not been significantly depleted by scattering into the final states.

The muon decay width is, from Fermi's golden rule:

This property has been used to check the -frequency dependence of the spontaneous emission rate as described by Fermi's golden rule.

The quantum mechanics problem is treated using time-dependent perturbation theory and leads to the general result known as Fermi's golden rule.

The rate of spontaneous emission (i.e., the radiative rate) can be described by Fermi's golden rule.

Fermi's golden rule dictates that the transition rate for the atom-vacuum (or atom-cavity) system is proportional to the density of final states.

This reduces the phase space volume of the possible states after scattering, and hence, by Fermi's golden rule, the scattering cross section goes to zero.

Thus, according to Fermi's golden rule, which says that transition probability is proportional to the overlap, optical transition strength is weakened.

The mixture can be expressed as a ratio of matrix elements (Fermi's golden rule relates transitions to matrix elements)

In the time-dependent perturbation theory for harmonic perturbations, the transition rate between the initial state and the final state is expressed by the Fermi's golden rule:

In the typical consideration of carrier scattering, this corresponds to the final state in Fermi's Golden Rule of scattering frequency:

In quantum physics, Fermi's golden rule is a way to calculate the transition rate (probability of transition per unit time) from one energy eigenstate of a quantum system into a continuum of energy eigenstates, due to a perturbation.

The density of states which appears in the Fermi's Golden Rule expression is then the joint density of states, which is the number of electronic states in the conduction and valence bands that are separated by a given photon energy.