CAPILLARY WAVES AT THE LIQUID-VAPOR INTERFACE - WIDOM-ROWLINSON MODELAT LOW-TEMPERATURE

We have examined in detail the structure and properties of the liquid- vapor interface for the two-dimensional Widom-Rowlinson model in its l ow-temperature regime. Various simplifying features permit the deducti on of several basic results. Included among these are (1) unambiguous definition of capillary wave modes with upper wavelength cutoff propor tional to rho(1)(-1/3) (rho(1) = liquid density); (2) wavelength dispe rsion of bare surface tension; and (3) nonmonotonic intrinsic density profile (i.e., that with vanishing capillary wave amplitudes). In an A ppendix we show how many of these results can be extended to the three and higher dimensional cases.