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The ultrafast nonradiative relaxation processes after photon excitation at 266 nm of Hg2 trapped in a cryogenic Ar matrix were studied by mol. dynamics with quantum transitions. Fourteen electronic surfaces and their corresponding couplings are included in ...
The adiabatic approximation is used to describe the electron states of weakly-one-dimensional quantum wires. A clear order is evidenced in the longitudinal optical (LO) phonon mediated transition rates with respect to the quantum numbers of the confined st ...
Selective photoluminescence experiments have been used to analyse the neutral donor bound exciton spectra in n type wurtzite GaN epitaxial layers deposited on 6H-SiC, Al2O3 and GaN substrates, In heterostructure layers, the existence of residual strain dis ...
Wide quantum wells, where the energy spacing between the first two energy levels is lower than the energy of the polar optical phonon, could represent the ideal condition to obtain a population inversion and the production of infrared lasers. On the other ...
The electron states of weakly-one-dimensional quantum wires are computed using the adiabatic approximation in the framework of the k . p theory and the envelope-function approximation. The computed transition rates of electrons from one confined state to a ...
The fluorescence of Ag8 in an argon matrix and in argon droplets is reported. This is the first unambiguous assignment of the fluorescence of a metal cluster larger than the tetramer, indicating that the excited state lifetime is longer than previously tho ...
Relative state-to-state cross sections for inelastic collisions between NO X (2) Pi(1/2) (upsilon = 20, J = 0.5, e or f) and He have been determined in a crossed molecular beam setup at a collision energy of 195 cm(-1). Efficient initial state preparation ...
Modern lasers now routinely allow experiments where large populations of highly excited molecules can be prepared with perfect quantum state selection. In a sense, the laser has become the physical chemist’s synthetic tool, allowing “optical distillation” ...
A theoretical investigation of the exciton formation process from free carriers in a single GaAs/Al1-xGaxAs quantum well is presented. The mechanism for the formation processes is provided by the interaction of the electrons and holes with phonons. The con ...
The authors present a new experimental method for measurement of collision-free infrared radiative lifetimes for single quantum states of a vibrationally excited sample. This method provides a more direct route to the infrared Einstein A coefficients than ...
