Physical review. B, Condensed matter
Two-dimensional virial and spin-wave coefficients of spin-polarized gases (H↑, D↑, He3 )
Valérie Lefèvre-Seguin, Henri Guignes, C. Lhuillier
Abstract
We present a quantum phase-shift calculation of the two-dimensional second virial coefficient ${B}_{2}^{2\mathrm{D}}$ and spin-wave characteristic parameters for spin-polarized quantum gases H\ensuremath{\uparrow}, D\ensuremath{\uparrow}, and $^{3}\mathrm{He}$. Emphasis is put on the study of quantum exchange effects which become essential in the 1-K range and below. The dependence of ${B}_{2}^{2\mathrm{D}}$ upon the nuclear polarization is analyzed. The calculation of statistics-independent coefficients is extended up to 50 K. The effect of a reduced dimensionality on the second virial and spin-wave coefficients is discussed and demonstrated by a comparison between 2D and 3D results. Two-dimensional bound states of helium dimers are estimated with the best present potential of Aziz et al. to be ${E}_{B}$${(}^{3}$He${\mathrm{\ensuremath{-}}}^{3}$He; 2D)=-0.88\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}5}$ K and ${E}_{B}$${(}^{3}$He${\mathrm{\ensuremath{-}}}^{4}$He; 2D)=-3.38 mK.