Radiative transition of [sup.5][D.sub.0]-[sup.7][F.sub.2] is electric-dipole transition .
Moreover, low phonon energy of tellurite glass promotes radiative transitions of rare earth ions.
There are two types of transitions that have been taken place from excited state 3, one is radiative transition
and other is non-radiative transition.
The general method relies on radiative transition rates [A.sub.ki] calculated with Cowan's codes (see Sec.
Percentage compositions of the levels and radiative transition rates have been calculated in the parametric fitting procedure.
This can be explained by excess carrier density accelerated radiative recombination through trap levels, assuming a nonradiative capture of carriers before radiative transition. Here, a barrier inherent behaviour of carrier transport mediated radiative recombination can also be implied.
Two spectral bands of photoluminescence have been observed within all types of samples: a narrower band of green luminescence (G-PL) peaked at 500 nm, which can be associated with interband radiative recombination, and a wider spectral band of red luminescence (R-PL) with a peak at 700 nm, which can be ascribed to deep trap mediated radiative transitions. Duration of the initial MW-PC transient component with instantaneous decay lifetimes of 2-10 ns is in the same time-scale with G-PL decay.
The energy of the emitted photon is equal to the energy difference [DELTA]E of the energy levels involved in the radiative transition (in a non-radiative transition, the excess of energy [DELTA]E contributes to the emission of an Auger electron).
The natural profile of a radiative transition is a convolution of energy distributions of each of the levels involved in the transition, which is a Lorentzian curve whose FWHM is equal to the sum of the FWHM of the two levels.
For the sake of simplicity, we consider only the radiative transitions
associated to electron and hole states in the same subband.
The QCD sum rules have been used for the radiative transitions
in charmonium and bottomonium cases [10-15].
He covers classical optics, quantum mechanics, radiative transitions
in atoms, photon statistics and antibunching, coherent states and "squeezed light," photon number states, resonant light-atom interactions, atoms in optical cavities, cold atoms, quantum cryptography and computing, entangled states and quantum teleportation.