A study of acoustic waves propagating along a fluid–solid plane interface, induced by thermoelastic excitation with a laser beam, is performed. The displacement of the interface in the time domain is predicted with an integration over frequency and on different Riemann sheets. The prediction, which includes the effect of the bulk waves induced by the thermoelastic excitation, can be performed at small distances from the heated region. For a bulk velocity in the fluid smaller than the shear wave velocity in the solid (water–glass configuration), and between the velocity of the shear and the compressional wave (water–plexiglass configuration), the poles that contribute to the displacement are identified by comparing the results of the integration in the different paths. A first analysis of the laser induced surface modes for water–porous ceramics configurations is performed in the context of the Biot theory. Measurements are presented.

The conduction band offset of the type II heterostructure CdS/ZnSe is determined from photoluminescence data of single quantum wells. The cubic quantum well samples have been grown by compound-source molecular-beam epitaxy. Photoluminescence spectra were measured at low temperatures and evaluated by fitting an effective mass model to the transition energies. A conduction band offset of (0.80 ± 0.1) eV and an effective electron mass for cubic CdS of (0.18 ± 0.05)m 0 were determined.

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