Thermal expansion of two dimensional itinerant nearly ferromagnetic metal

[Abstract] Thermal expansion of two-dimensional itinerant nearly ferromagnetic metal is investigated based on the recent spin fluctuation theory of magneto-volume effect for the three-dimensional weak ferromagnets. By assuming the double Lorentzian form of the spin fluctuation spectra, we have found T-linear thermal expansion coefficient is strongly enhanced. It increases rapidly in proportional to y^-1/2 as the magnetic instability point is approached. This result is consistent with the Gruneisen\u27s relation between the thermal expansion coefficient and the specific heat at low temperatures. We find that the thermal expansion coefficient is divergent independent of the value of finite y in 2-dimensional electron gas if we include the higher order terms of the wave-vector dependence of non-interacting dynamical susceptibility