Angular dependence of upper critical field in two-band Ginzburg-Landau theory

Generalization of two-band Ginzburg-Landau (GL) theory to the case of anisotropic mass is presented. The temperature dependence of the anisotropy parameter of upper critical field γc 2 (T) = Hc 2∥ (T) / Hc 2⊥ (T) and angular dependence of Hc2(θ, T) are calculated using anisotropic mass two-band Ginzburg-Landau theory of superconductors. It is shown that, with decreasing temperature anisotropy parameter γc2(T) is increased. Results of our calculations are in agreement with experimental data for single crystal MgB2. © 2007.