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 γc2(T)=Hc2∥(T)/Hc2⊥(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.