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Initial cleavage of a ring CC bond to form a trans .CHsub2SiHsub2Chsub2Chsub2. diradical is the most likely route from silacyclobutane to ethylene + silene, according to multiconfigurational self-consistent field wave functions and second order perturbation theory. The trans diradical is predicted to be a minimum on the MCSCF ground state potential energy surface. The addition of dynamic correlation leads to the disappearance of the transition state.

Compressively strained, square potential profile GaInAsP quantum wells (QWs) with grown on InP substrates are useful to improve 1.55-mum lasers. A new approach is based on the creation of a linear variation of the bandgap within the well, through linear variations in the As concentration. Effective density of heavy hold band states is reduced in such V-shaped structures, and overlap between electron and hole wavefunction is thought to be higher than narrow abrupt-shaped QWs.

The near-inertial oscillation (NIO) equation is used to analyze the propagation of waves through smaller scale, geostrophic eddies. It is predicted that an NIO with infinite horizontal scale would have frequency shfit -Kfomsuper2/Nsuper2. There is an effective vertical dispersion, with strength proportional to the eddy kinetic energy, because of the dependence of the frequency shift on msuper2.

An analysis accounts for the leakage of electron envelope function from a multi-quantum well (MQW) layer and finds the attenuation ratio of the MQW optical intensity modulator for 1.55 micrometer wavelength. Results for a modulator using InGaAsP compounds show an attenuation ratio of 12.6 decibels with a small residual absorption of 3.1 decibels for well number of 7 and well width of 9 nanometers at an applied voltage of -1.5 volts. The results agree with experimental observations for low field regions and show that the electron wave function leakage is large even for low applied fields.

Tunnel-current spectroscopy used to determine the quantum-mechanical energy levels of an electron in a quantum well in a magnetic field indicates the presence of concentrations of probability amplitude (wavefunction scarring). The experimental observations confirm the theoretical calculations. The spectra of the quantized energy levels, for systems that show chaotic motion, are not uniform and have fluctuations that are related to unstable periodic orbits. The orbits resemble scars in the wavefunction of the system.

A study was conducted to investigate the time evolution of the ground state wave function of an exciton in an ideal bilayer system within the framework of the effective-mass approximation. The variation amplitude and period of the modulus squared of the ground state wave function was found to increase with the in-plane electric field [F.sub.r] for a fixed in-plane relative coordinate r and fixed separation d between the electron and the hole layers.