  The deformation of a fluid-fluid interface due to the thermocapillary stress
induced by a continuous Gaussian laser wave is investigated analytically. We
show that the direction of deformation of the liquid interface strongly depends
on the viscosities and the thicknesses of the involved liquid layers. We first
investigate the case of an interface separating two different liquid layers
while a second part is dedicated to a thin film squeezed by two external layers
of same liquid. These results are predictive for applications fields where
localized thermocapillary stresses are used to produce flows or to deform
interfaces in presence of confinement, such as optofluidics.
